US3309636A

US3309636A - Electrically operated switch having improved armature and linkage means

Info

Publication number: US3309636A
Application number: US341593A
Authority: US
Inventors: Robert W Price
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1964-01-31
Filing date: 1964-01-31
Publication date: 1967-03-14
Anticipated expiration: 1984-03-14
Also published as: JPS4211521Y1

Description

March 14, 1967 R. W. PRICE 3,309,636

ELECTRICALLY OPERATED SWITCH HAVING IMPROVED ARMATURE AND LINKAG'E MEANS Filed Jan. 51, 1964 3 Sheets-Sheet l Fig.|'.

` 90 e9 84 sa 8| INVENTOR Rober W. Price WITNESSES ATTORNEY March 14, 1967 R. W. PRICE ELECTRICALLY OPERATED SWITCH HAVING IMPROVED ARMATURE AND LINKAGE MEANS Filed Jan. 3l, 1964 5 Sheets-Sheet 2 March 14, 1967 R, w, PRlCE 3,309,636

ELECTRICALLY OPERATED SWITCH HAVING IMPROVED ARMATURE AND LINKAGE MEANS FledJan. 31, 1964 3 Sheets-Sheet 5 United States Patent ELECTRICALLY OPERATED SWITCH HAVING IM- PRGVED ARMATURE AND LINKAGE MEANS Robert W. Price, Bloomington, Ind., assgnor to Westinghouse Electric Corporation, Pittsburgh, Pa., a corporation of Pennsylvania 'Filed Jan. 31, 1964, Ser. No. 341,593 Claims. (Cl. 335-155) This invention relates generally to switching equipment,

and more particularly to switches of the electrically operated type.

Y Generally speaking, prior art electrically operated switches employ a solenoid or solenoids as operating devices. My invention provides an improvement and advance in the art over the usual type of electr-ically operated switch construction in that the switch of my invention employs a rotary solenoid, that is, a solenoid in which the movable armature undergoes rotary motion in response to energization and deenergization of the coil. This type of solenoid crea-tes more force, is more compact in closed position, requires less space when its armature is in an opened position (stroke movement); and provides a hinge action lthat is easily adapted to the operation of moving linkages. The magnetic circu-it of my invention provides a high reactance to limit Vthe control current to a lower than usual value for both the inrush and steady-state alternating currents. The latter current is at least in part controlled by the gap dimensions machined into my solenoids magnetic circuit.

My electrically operated switch has other new and novel features, one of which is that it can be locked open or locked close, as well as electrically operated. In either the locked close or locked open positions, the switch cannot be energized from a control voltage source. In my apparatus, the shaft having the axis about which the armature rotates, is secured to the armature for rotation therewi-th, -is journalled for rotation in bearings at each end thereof, and has an operative connection secured thereto at each end. A manually actuated cam which pivots a lever which in turn is hinged to the solenoid armature shaft, provides for the three operating conditions. In both the locked close and locked open positions, this lever engages and opens a normally closed control switch to open the circuit which upon application of an energizing potential thereto would normally energize the solenoid. In the electrically operable position, herein called the automatic position, the cam actuated lever slides back and forth on the manually operated cam due to the rotating action of the solenoid, and does not engage the normally closed control switch. Furthermore, a spring is charged each time the magnetic solenoid is energized. When the solenoid is deenergized the springs stored energy is used to assist in opening the main switch contacts. The charged spring energy works in conjunction with the weight of the solenoids moving armature, and weight of the moving contact assembly. When deenergized, the solenoid armature falls open, and the moving contacts fall open, both being initiated by the spring but thereafter mutually aiding in the opening operation.

Furthermore, the linkage of my improved switch is not overtoggled by the action of the solenoid, as is usually the case in prior art devices. In my invention, the main switch contacts are held closed by the action of the solenoid force that moves the linkage to a near-toggle point. Under certain current conditions at the main contacts, this enables the springs stored energy to more easily open the main switch contacts when the solenoid is deenergized. When the main switch is carrying a heavy current, the magnetic blowing action of the main contacts would exert a pulling action to open the solenoid,

3,309,636 Patented Mar. 14, 1967 and if the linkages were overtoggle then the opening spring would have to overcome this force before any opening could be accomplished upon deenergizing the solenoid. To overcome this effect at heavy currents, it might become necessary to use other protective equipment in conjunction with my switch to handle the heavy currents, such as faults, to clear the circuit, then my switch would open after the fault was cleared.

Still further, my improved switch includes means automatically connected in the solenoid energizing circuit just prior to the complete closing of the armature which limits the coil current, and thereby provides for a lower Operating temperature with sustained energization.

Accordingly, a primary object of my invention is to provide a new electrically operated switch containing improvements over any electrically operated switch know existing in the art.

A further object is to provide a new and improved electrically operated switch utilizing a rotary solenoid.

An additional object is to provide a new and improved electrically operated switch in which energization of a control solenoid moves linkage to a' near-toggle point resulting in closing the main switch contac-ts and increased tensioning of a spring, and the energy stored in the tensioned spring is used to open the main switch contacts when the solenoid is deenergized.

Still a further object is to provide a new and improved electrically opera-ted switch having locked open, automatic, kand locked close operating positions.

These and other `objects Vwill become more clearly apparent after a study of the following specification, when read in connection with the accompanying drawings, in which:

FIGURE l is a View partially in cross-section of a switch illustrating an embodiment of the invention;

FIGS. 2A, 2B and 2C are perspective, side-elevational, and underneath views of the operating solenoid, associated linkages and control switch mechanisms controlled by the solenoid and a manually operable cam;

FIGS. 3A, 3B and 3C are views of the Apositions of the linkages employed in the operating mechanism while the switch is in On Automatic, and Oifpositions respectively as manually selected, On corresponding to the aforementioned locked close position, and Off corresponding to the aforementioned locked open position; and

FIG. 4 is an electrical circuit diagram of my electrically operated switch.

Referring now to the drawings, in which like reference numerals are used throughout to designate like parts, for a more detailed understanding of the invention, and in particular to FIG. l thereof, there is shown a switch generally designated 10 enclosed in a metal tank 11 which is provided with an insulating liner 12 and which is surmounted by top casting 13. Switch 10 has two bushings 14 mounted in the top cast-ing 13, each with a conducting stud passing through the bushing. An incoming line enters through the Ibushing 14, only the inner end of which is shown. The stud in bushing 14 terminates inside the tank as a threaded stud portion or threaded rod, which is electrically connected to a fixed contact in a manner hereinafter described in detail. The other of the two bushings, each with the aforementioned conducting stud passing therethrough, also has a threaded stud portion terminating at its bottom for electrical attachment to a xed contact, the other bushing 'being designated 14.

The contact assembly is comprised of iixed contacts and a movable contact bar, all mounted on a common support attached to the top casting. Specifically, t-he contact assembly includes a -pair of spaced apart, parallel extending elongated support members which are preferably cast as a single unit, one of these members being shown at 21; the two support members 21 may be formed integrally with each other in a cast support structure of suitable insulating material having sufficient mechanical strength, the two support members 21 having oppositely extending arm mounting portions 22 which are secured by bolts 23 to bosses 24 in the aluminum casting 13. The two bosses 24 are oppositely disposed with respect to each other. Each of the support members 21 has an offset portion 26 at the lower end thereof, the two supports 21 extending down near the previously described

bushings

14 and 14. Preferably, the insulating structure containing the arms 2-1 has cross bars, cross walls or cross portions between the arms to give mechanical strength to the structure. The forementioned spacers between the two arms 21 may be located at any convenient positions. On the outside of each arm 21 there is secured a fixed contact mount 27 secured as by rivets, not shown for convenience of illustration, each fixed contact mount comprising an elongated fiat conductor, the flat conductor lying partially on the upper portion of the support 21 and partially on the offset portion 26, the fiat conductor being designated 28. Each mount 27 includes an integral stud 29 on the upper portion for directly supporting the fixed contacts, as hereinafter described, and each mount 27 includes an integral connector portion 31 on the portion of the mount adjacent the offset portion 26. The connectors 31 are attached to the aforementioned bushing studs respectively as by the nuts 32.

A stationary contact assembly is provided on each mount 27, each assembly comprising a pair of opposed finger contacts 33 and 34, each pair of finger contacts having its corresponding members held at the upper end in opposed gripping relationship to the stud 29 by means of

compression springs

36, 37, each pair of

springs

36, 37 encircling a pin 38 extending through substantially aligned bores in the central portions of corresponding pairs of finger contacts, each spring being compressed between one of the finger contacts and a washer and pin assembly, there being washer and pin assemblies at both ends of each pin 38, the washer and pin assemblies being designated 39. The lower end of each finger contact has an elongated striker contact portion 48 on the inner side thereof and the lower ends of the pairs of finger con- .tacts are dared outwardly with respect to each other. This structure effects a gradual spreading apart action of the finger contacts of each pair under the impact of the movable contact 4bar hereinafter described, as it is forced upwardly between the fixed contact finger pairs.

A lug 18 secured to stud 2'9 has a dexible electrical connector 19 secured thereto, the ends, not shown, of connector v19 being soldered or otherwise secured to fingers 33 and 34 respectively.

The movable contact assembly is provided for engagement with the fixed contacts, and comprises a pair of parallel insulating support bars, one of these bars being shown at 41, bar 41 being connected at one end to the offset portion 26 of the support 21 by means of a pin 42 which is common to both the support bars 41 and is connected between the insulating support members or offset portions 26. Pin 42 may be of insulating material, may extend through aligned circular bores in offset portions 26, and may have cotter pins in the ends thereof adjacent the outer faces of offset portions 26. The other ends of the support bars 41 are connected together by a spacer bracket, not shown for convenience of illustration, which is riveted to the support bars 41 at 43 and 44, and is riveted to the contact member or contact bar 45, by rivets not shown. The elongated contact bar or contact member 4'5 has tapered conta-ct portions at each end, one of these tapered contact portions being shown at 46, the contact members having slightly tapered surfaces as aforementioned with respect to the normal surfaces of the bar, to facilitate engagement with the aforementioned contact fingers 33 and 34. The movable contact portions 'tension on the contacts.

46 are simultaneously engaged by the corresponding fixed contact lingers on both support arms 211 when the insulating contact supporting bars 41 are pivotally rotated upwardly about pin 42 to a substantially horizontal closed position from a lowermost fully opened position. It is to be noted lthat while the switch is in fully opened position the minimum distance between any oppositely disposed points of the striker contact portions 48 is less than the thickness of contact portions 46 at the tapered edges thereof, as a result of the action of

springs

36 and 37; this structure provides for the upper edges of tapered contact portions 46 to initially strike the striker portions 48 of the fixed contacts at the lower ends; thereafter continued upward motion of the contact arm 45 effects a wiping action between the fixed contact portions 48 and movable contact portions 46, and a resulting gradual spreading of the fixed contact finger pairs. Thus initial contact is always made near the ends of both the movable and fixed contacts, which are wiped clean as the closing cycle is completed, to thus minimize the resistance even after repeated operation. Further, the final current path is through portions of the surfaces of the contacts which are not subject to initial striking action.

An operating mechanism generally designated 50 iS mounted in the top casting 13. This operating mechanism Stl may be regarded as starting with the movable Contact arms 41 and including the upwardly extending insulating pull rod 52, the bottom end of which is connected to the movable contact assembly in a manner hereinafter described. Insulating rod 52 has a threaded portion 53 at the upper end thereof in threaded engagement with internal threads in a metallic cylindrical extension 54 having lock nut 55. The upper end of the cylindrical metallic portion 54 has a slot therein through which passes a pin 56, the pin 56 forming one pivot point of a rocker member or lever 58. The rocker member 58, generally triangular in shape, is pivoted for rotation about a pin 61 which passes between the two supporting arms 21. Rocker member 58 may be held in position as by a spacer or spacers and by providing an extended arm portion which slides against an adjacent outer surface of one of the supporting posts 21. The upwardly extending apex portion of the triangular shaped rocker member 58 has pivotally connected thereto at pin 62 a lever arm 63. The other end of the lever arm 63 has pivotally connected thereto at pin 64 a driving lever 65 which is operatively connected to the solenoid in a manner to be made more clearly apparent hereinafter, and a further lever 66 also has one end pivotally connected at 64, the other end of lever 66 being journalled for rotation about a fixed pivot point 67, which may be a stud extending from a boss portion of the top casting 13. It will be noted that the

levers

65, 66 and 63 all pivotally connected at pivot pin 64 constitute a toggle mechanism, and the toggle feature of this lever assembly will be described more fully hereinafter, and the uses of the same.

The aforementioned pull rod 52 is attached to the previously described movable contact assembly by means of a resilient coupling operable to absorb impact energy when the movable contact portions 46 engage the fixed contacts during a switch-closing operation, to urge the movable contact portions 46 into full engagement with the fixed contacts, and to provide for a slight amount of overtravel of the pull rod necessary to provide spring Specifically, the resilient coupling assembly comprises a guide block 71 suspended between the parallel support arms 41 by means of a pair of opposed pins extending from the block 71 into aligned bores in arms 41, one of these pins being shown and designated 72. The pins 72 are connected to the arms 41 in bores at points substantially midway along the length of the arms 41 between the pivot pin 42 and the aforementioned spacer bracket which is riveted at 43 and 44 to arm 41, and which has riveted thereto the moving contact bar 45. The block 71 is centrally apertured to slidably receive the lower end of pull rod 52. A saddle bracket 74 having

legs

75 and 76 is centrally apertured for the passage of the pull rod 52, and is secured to the block or trunnion 71 as by crimping overhanging extended lug or stud portions on the upper and lower sides of the block member 71, FIG. 1. The lower end of the pull rod 52 is connected'to the

legs

75 and 76 of the saddle bracket 74 by means of a pin 77 passing through the

legs

75 and 76 and passing through an aperture 73 in the pull rod therebetween. A washer 78 is disposed on the end of the pull rod and is held abutting against the pin 77 by the pressure of coiledspring 79, the upper end of which abuts against the aforementioned block 71. It will be seen that the upward movement of the pull rod 52 in a switch-closing action will pivotally move the movable contact arm 41 upwardly around pivot pin 42, causing the movable contact assembly to strike the fixed contact assembly, and that thereafter compression of the spring 79 between the washer 78 and the lower face of the block 71 relieves the impact force of the operation.

Trunnion 71, saddle bracket 74 and spring 79 do more than relieve the impact force. The moving contact 45 is stopped in its closed position by engaging the insulating support 21. This would mean that the solenoid `armature would not be permitted to seat if the pull rod 52 was adjusted too short.

Members

71, 74 and 79 allow a cushioning effect for wear in linkage at pivot points 64,-,62, 61, 56, and more especially at pivot points 42 and 72 through operation. A new switch compresses spring 79 while a worn switch would depend somewhat on the action of spring 79 to drive the moving contact home when no further motion from the solenoid was available. In essence,

members

71, 74 and 79 insure a longer useful switch life, although the switch would function without this feature through readjustment of pull rod 52.

As previously stated, the main switch contacts of the instant invention are closed by means of a magnetic solenoid when the solenoid is energized, and the main switch contacts are opened by stored energy in the form of a spring when the solenoid is deenergized. The contacts may also be closed and locked closed by a manually operable lever outside the switch housing, and the contacts may be locked open by the same manually operable lever. The aforementioned lever 65 constituting part of the toggle mechanism of

levers

66, 65, 63 and pivot pin 64, is pivotally connected at pin 81 to a short lever arm' 82 which is secured to the shaft on which the armature 83 is secured, the armature shaft 84 being shown as having the extended end portion flattened in shape, to emphasize that the lever 82 is fixed to the armature shaft and rotates therewith; the armature shaft has secured thereto on the opposite end thereof an additional lever 85, which also rotates with the armature shaft and with the armature. The lever 85 has pivotally connected thereto by pin 86 an additional elongated lever 87 which has a .precisely shaped end portion as seen in FIG. 1, having a slot 88 therein. Lever 87 also has a cam portion 105, FIG. 2A. The slot and cam portion are provided for purposes to be made more clearly apparent hereinafter. The solenoid is seen, FIG. 1 and elsewhere, to have a coil 89 and to have a stationary field pole portion 90 which is preferably of laminated construction.

Particular reference is made now to FIGS. 2A, 2B and 2C where the solenoid and associated parts of the apparatus are shown in greater detail. The solenoid is seen to have a pair of normally closed microswitches generally designated 91 and 92 mounted adjacent thereto, the microswitches having

lever arms

93 and 94 respectively. The aforementioned stationary eld pole 90v of the solenoid assembly is seen to have secured thereto a pin or stud 95 on which is pivotally mounted a generally arcuate-shaped lever 96, the lever 96 being retained on the pin 95 as by washer 97 and cotter pin 98. When the armature 83 is closed by energization of the coil 89, a pin or 6 stud 99 carried by the end of the armature y83 presses against the adjacent portion of the lever 96, causing the opposite end 101 of'lever 96 to press against the switch arm 94 opening the contacts of the switch 92. Connected across the contacts of the switch 92 is a resistor 103, FIG. 4, which is seen to be in series with the coil 89. The switch 92 and resistor 103 provide for low temperature operation of the solenoid coil when it is continuously energized, in a manner which will be more clearly apparent hereinafter, but it may be stated briefly here that this is accomplished by the lever 96 which is actuated by the solenoid armature just prior to seating. This lever 96 opens the normally closed control switch 9-2, inserting the resistance 103- in series with the solenoid coil S9. This resistance lowers the impressed voltage across the solenoid coil and consequently lowers the current through the coil. This is feasible since the sealing force for such a magnet is far in excess of that required at the time when the solenoids armature is seating. This feature enables a physically smaller actuating solenoid to be used to create the required closing force without exceeding a speci-fied temperature rise while continuously energized.

The lever arm 93 of switch 91, which is also normally closed, is seen to be actuated by the carn portion of lever- 87, the cam portion beingdesignated 105. Switch 91 is also in series with the winding 89, and when the apparatus is locked open or locked close in a manner to be hereinafter described, the cam portion 105 pressing against the switch arm 93 opens the circuit to solenoid 89 so that the main switch cannot be electrically operated. The spring tension of arm 93 closes switch 91 when the force of the cam portion 105 is removed therefrom. Mounting bracket means for the solenoid assembly is shown generally at 106, and may be secured to the top casting 13 in any convenient manner. It is seen that the solenoid shaft 84 rotates in journalled bearings in the mounting means 106, and that there is secured to the shaft 84 the aforementioned lever arm 82. The side elevation view of FIG. 2B shows the bracket member 108 secured to the aforementioned solenoid 'mounting 106 'by bolt 109, and the bracket 108 is also secured to the two microswitches by a pair of bolts, one of these being shown at 110, which pass through transverse bores in the microswitches.

In FIG. 2C, to which particular reference is made, a bottom view of the solenoid assembly is shown, while, for convenience of illustration, the solenoid is energized or locked with the armature rotated to seated position, and the aforementioned lever 85 is seen to be fixed to the solenoid shaft 84 for rotation therewith, the lever 85 having at the other end` thereof pivotally securedl for movement therewith by pin 112 the aforementioned lever 87. VThe lever 87 is seen to have secured thereto as by welding a short arm 114 to which is secured one end of a strong spring 115, the other end of the spring 115 ibeing secured to a stud 116 extending from the bracket 108 or from the solenoid mounting, the stud 116 being secured to the top casting 13 or the mounting in any convenient manner, as by riveting.

As previously stated, the switch of my invention is opened -by stored energy in the form of a tensioned spring when the solenoid is deenergized. Accordingly, it is seen that closing of the armature 83 to the position shown for example in FIG. 2B moves the pin 11 2 backward or to the right, FIG. 2C, moving the lever 87 and arm 114 to the right, FIG. 2C, and causing the spring 115 to be further tensioned or elongated. Since, as previously stated, the toggle

mechanism including levers

63, 65 and 66 is brought only to a near toggle point, when the solenoid coil 89 is deenergized, the tension of spring 115 causes armv 87 to move to the left, FIG. 2C, rotating the solenoid shaft 84 in a counterclockwise'direction, FIG. 2B,rotating the lever arm 82 upward, FIG. 2B and FIG. l, and this causes pivot point 64 to move upward, FIG. l, with the result that pivot point 62 is moved to the left,

FIG. 1; as a result there is movement of the rocker arm 58, point 56 is moved downward and the connecting rod 52 causes the arm 41 to move downward, disengaging the movable contacts 46 from the nger contacts 33 and 34.

Assuming by way of description that the main switch is open and it is desired to close it, and assuming further that the manual control arm 118, FIG. 3B, is in the Automatic position so that the electrical circuit through the solenoid 819 is completed through 'both normally closed

switches

92 and 91, FIG. 4, in series with the winding 89, by applying a source of potential across the

leads

121 and 122, FIG. 4, solenoid coil S9 is energized, causing armature 83 to swing to the closed position shown in FIG. 1, causing lever arm 82 to swing Idownward or in a clockwise motion and carry pivot pin 81 downward, pulling the lever 65 downward, pulling pivot pin 64 downward, and causing the right-hand end of lever 63 seen in FIG. 1 to move to the right carrying with it pin 62, causing the rocker arm 58 to rotate in a clockwise direction about the pin 61, moving pivot pin 56 upward, and carrying with it the connecting rod 52. This causes the lever arms 41 to pivot in a counterclockwise direction about pivot pin 42, FIG. l, and to -move the contact portions `46 into closed position with the contact tinger arms 33 and 34.

Particular reference is made now to FIGS. 3A, 3B and 3C, together with FIG. 4, for a bet-ter understanding of the use of the manual control arm 118 to put the main switch in an Automatic position where it can be closed lby energizing the solenoid 89 or opened by deenergizing the solenoid 89, and also to put the main switching apparatus in a locked-on or locked-closed position, and in a locked-off or locked-open position. Arm 118 is shaped to be conveniently manipulated lby the conventional hook stick. In FIG. 3A, the manually operable' lever 118, which is external to the top casting 13, is seen to be -movable with respect to a switch position indicator plate 124 secured to the side of the top casting and having On, Automatic and Oil positions as. shown. A shaft 125 is secured to the manually operable lever 118 to be turned therewith, as by a set screw, not shown for convenience of illustration. The shaft V125 extends through the wall of the top casting 13, and has onthe inside end thereof a cam 126i, secured to shaft 125 for rotation therewith. A pin 127 secured to or formed integrally with the cam face 126 at a predetermined position thereon moves in the aforemention sl-ot 88 in the lever 87; the pin 127 is secured against inadvertent disengagement with the slot as by the washer 128 and cotter pin 129, FIG. 2A. The movement of the lever 87, then, is controlled at least in part by the position of the 4pin 127 in the slot 88. FIG. 3A shows the levers in a locked on position, that is, with the armature locked closed as in the armature position of FIG. 2A, and the electrical circuit to the armature coil 89 lbroken by the opening of the switch 91. It should be understood however, that FIG. 2A does not show lever 118 in locked on position; in FIG. 2A pin 127 is in the outer end of slot 88 where it was free to move as a result of the energization of coilr89.

When lever 118 is thrown to On position, pin 127 pressing against the left-hand end of slot 88, FIG. 3A, yforces lever 87 to the left, forcing pivotally connected lever 85 to turn the armature shaft and armature to a closed position. No further movement is thereafter possible. The pin 127 is shown to be at the left-hand extremity of the slot 88, FIG. 3A, and in this position the spring 115 is fully tensioned, FIG. 2C, the armature 83 fits snugly against the stationary field member 90, the lever 82 is rotated in a clockwise direction about shaft 84 as far as it will go, pulling the lever 65 and pivot point 64 down, causing pivot pin 62 to be moved to the right, FIG. 1, as far as possible, raising pivot pin 56 and causing the main switch contacts to be snugly engaged.

The lever 87 in the locked-on position has the cam portion 10-5 thereof pressing against switch arm 93, opening switch 91 so that potential cannot be applied to the solenoid 89 by way of

leads

121 and 122. Switch arm 93 is not shown in FIG. 3A for convenience of illustration.

Particular reference is made now to FIG. 3B where the manual control is shown in the Automatic position and coil 89 is assumed to be deenergized, and it is seen that the pin 127 is approximately centrally located in the slot 88, permitting the pin 127 to move `freely in response to energization of the solenoid coil 89.

In FIG. 4, which shows the lever and control switch positions with the manual control in Automatic position and the solenoid 89 deenergized, it is seen that both

switches

91 and 92 are closed, switch 91 completing the circuit to the coil 89 and switch 92 cutting the resistor 193 out of the circuit by short-circuiting the same. It is seen that main switch contacts 45 are open.

FIG. 1, it should be noted, shows the lever 118 in Automatic position and the solenoid 89 energized. The main switch is closed.

Particular reference is made now to FIG. 3C, where the manual control lever 118 is shown in the lockedoll or locked-open position. It is seen that the pin 127 hask moved to the extreme right of the slot 88. Lever 87 cannot move to the left, and accordingly the solenoid magnetic circuit cannot be closed. Furthermore, cam portion of lever 87 presses against microswitch arm 93, opening switch 91 and preventing energization of coil 89. The microswitch arm 93 is omitted in FIG. 3C for convenience of illustration.

In summary, lever 118 cannot be used -to open the switch proper when it is energized. It can be used to lock closed the switch when it is energized however. In other words, when the switch is energized, lever 118 can be moved from Auto to On and from On to Auto, but not from Auto to Olii It can be moved from Oil to Auto, however, when voltage is applied.

To attempt to move from Auto `to Off when switch is energized (solenoid) will result in a deformation of lever 87. v

Moving from OIT to Auto when the voltage is applied will result in a jerk on the operating hook-stick with possible damage to lever 87, with mechanical slowing of the main closing contacts.

The outer corners of cam 126 serve a purpose. These corners limit travel of cam `by engaging head casting. This cam together with pin 127 form a toggle action joint with lever 87. The interference of the cams points prevent further rotation and consequent motion of lever 87 to relieve rotary motion of lever 85.

There has been provided, then, apparatus well suited to accomplish and fulfill the aforedescribed objects of the invention. As previously stated, the main switch is closed by means of a magnetic solenoid when the solenoid is energized, and the main switch is opened by stored energy in the form of a tensioned spring, when the solenoid is deenergized. The rotary solenoid creates more force, is more compact in closed position, requires less space when its armature is in the open position (stroke movement), and provides a rotary hinge action that is easily transmitted to the movable linkages. The solenoids magnetic circuit provides a high reactance to limit the control current to lower than prior art values for both the inrush and steady-state alternating currents. The latter current is controlled in part by the gap dimensions of the solenoids magnetic circuit. If desired, small shading coils, not shown, can be placed in the magnetic circuit to suppress vibration and to prevent chattering.

The switch of my invention, as previously stated, can be locked-open or locked-closed, as well as operated electrically or automatically. In either of the locked-closed or locked-open positions, the solenoid which controls the armature gap is much larger.

main'switch cannot be energized from a control voltage source. This is made possible by the aforedescribed manu ally actuated cam, that controls a lever which is hinged to the solenoids shaft. This lever engages a normally closed switch to open the control circuit in both the locked closed, and locked opened positions. In the electrically operable position, the cam-actuated lever can slide back and forth on the manually operated cam due to the rotating action of the solenoid, and does not engage the normally closed control switch. As previously stated, a spring is charged each time the magnetic solenoid is energized, the spring being designated 115, FIG. 2C. When the solenoid is deenergized, the springs stored energy is used to open the switch.

As previously stated, another feature of my invention is that I provide means for insuring low temperature operation of the solenoid coil when it is continuously energized. I provide a normally closed switch connected in parallel with a current limiting resistor in series with the solenoid coil. The switch is mechanically opened lby the moving armature of the solenoid just prior to the time it seats magnetically. When the switch opens, the resistor is connected in series with the solenoid coil. The load current develops an I-R drop across the resistor, `resulting in a reduced voltage being impressed across the solenoid. At no time is the continuity of the circuit interrupted.

Because magnetic solenoids have an approximately inverse pull-gap characteristic, that is, the smaller the magnetic armature gap, the greater the closing force, it is feasible to reduce the impressed voltage when the solenoids armature is almost closed and still retain the same holding force as developed by the solenoid when its Due to the fact that the circuit impedance has been increased by the insertion of the resistance by the opening of the switch, the load current is reduced in value, as long as the solenoid is closed or seated The heating of the solenoid is thus reduced, the heating -being proportional to the square of the current. This changing of the circuit constants limits the load current to a value which will permit the solenoid to be operated continuously without exceeding` its designed temperature rise. y

Resistor 103 may be mounted inside of housing 11 in any convenient position. It mayconsist of two parallel connected 100 ohm resistors of suitable wattage to give 50 ohms, each mounted near a bushing 14 and extending downward of casting 13.

The two parallel connected resistors give greater surface for cooling; also the use of two resistors limits the distance which they extend down into the tank towards the contacts.

The term near toggle point'as employed herein and in the claims appended hereto means a condition approaching and including dead center for the pivot pin 64.

Movement away from the near toggle point means movement of pin 64 in an upward direction.

Preferably, tank 11 is filled with oil to a level well above contacts 46-33-34.

As noted, spring 115 is under tension at all times, both when the solenoid is energized or deenergized. Its characteristic should be fairly flat so that loading of the solenoid is not affected 'by the load of closing the contacts and a sharply increasing load due to the spring.

Whereas I have shown and described my invention with respect to an embodiment thereof which gives satisfactory results, it should be understood that changes may be made and equivalents substituted without departing from the spirit and scope of the invention.

I claim as my invention:

1. Switch apparatus comprising, in combination, fixed conta-ct means, movable contact means movable into engagement with the fixed contact means to close the switch land movable out of engagement with said fixed contact means to open the switch, operating means including a toggle mechanism for effecting movement of the movable contact means into engagement with the fixed contact means when the toggle mechanism is moved at least to a near toggle point and out of engagement with the fixed contact means when the toggle mechanism is moved away from the toggle point by at least a predetermined amount, solenoid actuated means including a solenoid having a rotatable armature and a rotatable shaft secured thereto for rotation therewith, link means operatively connecting the toggle mechanism to the rotatable shaft for moving the toggle mechanism at least to said near toggle point when the solenoid is energized to effect a closing of the switch, and spring means operatively connected to the solenoid actuated means and including a spring normally tensioned to a first degree while the solenoid is deenergized, said spring being tensioned to a second degree greater than said rst degree when the solenoid is'energized, said spring when the solenoid is thereafter deenergized causing the toggle mechanism to move away from the near toggle point by said predetermined amount and open said switch.

2. Switch apparatus comprising, in combination, fixed Contact means, movable contact mean-s movable into engagement with the fixed contact means to close the switch and movable out of engagement with said fixed contact means to open the switch, operating means including a toggle mechanism for effecting movement of the movable contact means into engagement with the fixed contact means when the toggle mechanism is moved at least to a near toggle point and out of engagement with the fixed contact means when the toggle mechanism is moved away from the toggle point by at least a predetermined amount,

solenoid actuated means including a solenoid, the solenoid actuated means being operatively -connected to the toggle mechanism for moving the toggle mechanism at least to said near toggle point when the solenoid isenergized to effect a closing of theswitch, spring means operatively connected to the solenoid actuated means and including a spring normally tensioned to a first degree while the -solenoid is deenergized, said spring being tensioned to a second degree greater than said first degree when the solenoid is energized, said spring when the solenoid is thereafter deenergized causing the toggle mechanism to move away from the near toggle point by said predetermined amount and open said switch, and manually operable means for locking the movable contact means in engagement with the fix-ed contact means while preventing the Isolenoid from being thereafter energized.

3. Switch apparatus comprising, in combination, fixed contact means, movable contact means movable into engagement with the fixed contact means to close the switch and movable out of engagement with said fixed Contact means to open the switch, operating means including a toggle mechanism for effecting movement of the movable'contact means into engagement with the fixed contact means when the toggle mechanismis moved at least to a near toggle point and out of engagement with the fixed Contact means when the toggle mechanism is moved away from the toggle point by at least a predetermined amount, solenoid actuated means including a solenoid, the solenoid actuated means being operatively connected to the toggle mechanism for moving the toggle mechanism at least to said near toggle point when the solenoid is energized to effect a closing of the switch, spring means operatively connected to the solenoid actuated means and including a spring normally tensioned to a first degree while the solenoid is deenergized, said spring being tensioned to a second degree greater than said first degree when the solenoid is energized, said spring when the solenoid is thereafter deenergized causing the toggle mechanism to move away from thenear toggle point by said predetermined amount and open said switch, and manually operable means for, while thesolenoid is deenergized, locking the movable Contact means out of engagement with the fixed contact means while preventing the solenoid from being thereafter energized. n

4. Switching apparatus comprising, in combination,

fixed contact means, movable contact means movable into and out of engagement with said fixed contact means, operating means including a toggle mechanism for effecting movement of the movable contact means into engagement with the fixed contact means when the toggle mechanism is moved to a near toggle point and for effecting movement of the movable contact means out of engagement with the fixed contact means when the toggle mechanism moves away from the near toggle point by at least a predetermined amount, solenoid means including a solenoid having a rotatable armature and a rotatable shaft secured thereto for rotation therewith operatively connected to the toggle mechanism, and normally tensioned spring means operatively connected to the armature and to the toggle mechanism, the spring means being additionally tensioned when the solenoid is energized and the armature is rotated in a first direction, the armature rotating in a second direction when the solenoid is deenergized, said spring means when the solenoid is deenergized causing the toggle mechanism to move away from the near toggle point by at least said predetermined amount.

5. Apparatus according to claim 4 having the solenoid means mounted so that the rotatable armature swings downward when the solenoid is deenergized, and in which the force of gravity on said armature adds to the force of the spring means when the solenoid is deenergized.

6. Apparatus according to claim 4 having the movable contact means so mounted that the movable contact means moves downward when the movable contact means moves out of engagement with the fixed contact means, and in which the force of gravity on the movable contact means adds to the force of the spring means when the solenoid is deenergized.

7. Switching apparatus comprising, in combination, xed contact means, movable Contact means movable into and out of engagement with said fixed contact means, operating means including a toggle mechanism for effecting movement of the movable contact means into engagement with the fixed contact means when the toggle mechanism is moved to a near toggle point and for effecting movement of the movable contact means out of engagement with the fixed contact means when the toggle mechanism is moved away from the near toggle point by at least a predetermined amount, solenoid means including a solenoid and a movable armature operatively connected to the toggle mechanism for, when the solenoid is energized, moving the toggle mechanism to said near toggle point, spring means operatively connected to the toggle mechanism for, when the solenoid is deenergized, moving the toggle mechanism away from the near toggle point by at least said predetermined amount, electrical circuit means including a normally closed switch connected to the solenoid for applying an energizing potential to the solenoid, a resistor connected in parallel with said switch, and means operatively connected to the solenoid means and responsive to movement of said armature as a result of the application of an energizing potential to the solenoid for opening said normally closed switch at a predetermined instant before the armature of the solenoid means has completed its mechanical travel to thereby connect said resistor in series with the solenoid.

8. Switching apparatus comprising, in combination, xed contact means, movable contact means movable into and out of engagement with the xed contact means, operating means including a toggle mechanism for effecting movement of the movable Contact means into engagement with the fixed contact means when the toggle mechanism is moved to a near toggle point and for effecting movement of the movable contact means out of Iengagement with the fixed contact means when the toggle mechanism is moved away from the near toggle point by at least a predetermined amount, solenoid means including a CQ and 2l mOi/,abile armature, said movable armature being operatively connected to the toggle mechanism for moving the toggle mechanism to said near toggle point when the coil is energized, normally tensioned spring means operatively connected to the toggle mechanism, said spring means being additionally tensioned when the armature moves in response to the energization of the coil, electrical circuit means including a normally closed switch operatively connected to the coil for applying an energizing potential to the coil, resistor means operatively connected across said normally closed switch, and means responsive to movement of the armature and operatively connected to said normally closed switch for opening the contacts of said last-named switch at an instant before the limit of movement of the armature is reached to thereby connect said resistor means in series with said coil, said coil thereafter maintaining the toggle mechanism at said near toggle point while the energizing potential is applied to the coil, the removal of the energizing potential from the coil releasing said spring means which thereupon moves the toggle mechanism away from said near toggle |point by at least said predetermined amount.

9. Switch apparatus comprising, in combination, separable contact means, operating means including solenoid means and toggle means movable in response to energization and deenergization of the solenoid means for closing and opening said contact means, spring means operatively connected to the toggle means for assisting in moving the toggle means when the solenoid means is deenergized to thereby open the contact means, and manually operable cam means operatively connected to the solenoid means and to the toggle means for selectively locking the contact means in closed and opened positions in accordance with the position of the manually operable cam means, said cam means preventing energization of the solenoid means while the contact means is selectively locked in one of said opened and closed positions.

10. Switch apparatus comprising, in combination, separable contact means, operating means for opening and closing said contact means, said operating means including solenoid means having a coil and a movable armature responsive to energization and deenergization of the coil, the armature having open and closed positions while the coil is deenergized and energized respectively, said operating means including toggle means operatively connected to the armature and to the separable contact means, said contact means being closed while the toggle means is at a near toggle point, said Contact means being open while the toggle means is away from the near toggle point by at least a predetermined amount, the energization of said coil causing said armature to move to a closed position and said toggle means to move to said near toggle point, normally tensioned spring means operatively connected to said armature and to said toggle means, the movement of said armature as it closes causing said spring means to be additionally tensioned, the deenergization of the coil releasing the spring means whereupon the spring means assists the armature in moving to the open position and causes said toggle means to move to a position away from the near toggle point by at least said predetermined amount, electrical circuit means connected to the coil for applying an energizing potential to the coil, the electrical circuit means including a normally closed switch, and manually operable lever means operatively connected to the armature and to the toggle means, said manually operable lever means having tirst, second and third positions corresponding respectively to locked-closed, automatic, and locked-open positions of the separable contact means, said manually operable lever means being also operatively connected to said normally closed switch and opening said switch while the lever means is in the locked-closed position and' in the locked-open position to thereby interrupt the circuit to the coil of the solenoid means and prevent the application of an energizing potential to the coil.

1l. Switching apparatus comprising, in combination, separable contact means, a toggle mechanism operatively connected to the contact means whereby the contact means are closed while the toggle mechanism is at Ia near toggle point and said contact means are open while the toggle mechanism is moved away from the near toggle point by at least a predetermined amount, solenoid means including a coil and a rotatable armature operatively connected to the toggle mechanism, said rotatable armature moving the toggle mechanism to said near toggle point when the coil is energized, spring means operatively connected to the toggle mechanism for moving the toggle mechanism away from the near toggle point when the solenoid is deenergized, electrical circuit means connected to the coil for applying an energizing potential to the coil, the electrical circuit means including first and second normally closed switches both in series with said coil, resistance means connected in parallel with the contacts of the rst switch, means operatively connected to the armature for opening the rst switch at an instant before the rotatable armature reaches the limit of its travel after the coil is energized whereby said resistance means is inserted in series with said coil, and manually operable lever means operatively connected to said armature land to said toggle mechanism, the manually operable lever means providing first, second, and third settings corresponding to locked-closed, automatic, and locked-open conditions of the separable contact means, said lever means being operatively connected to said second switch whereby while the manually operable lever means is selectively in the first and third settings corresponding to locked-closed and locked-open contact conditions to open the second switch thereby opening the circuit to the coil and preventing the application of an energizing potential to said coil.

12. Switching apparatus comprising, in combination,

separable contact means connected in the circuit to be switched, electroresponsive means including a circuit for energizing the same, lever means operatively connecting the electroresponsive means to the contact means for closing the contact means when the electroresponsive means is energized, spring means operatively connected to the lever means for opening the contact means when the electroresponsive means is deenergized, and manually operable means operatively connected to the lever means and to the electroresponsive means for, at a selected manual setting, locking the lever means in a position to maintain the contacts closed and at the same time opening the circuit to the electroresponsive means, for at a selected other manual setting locking the lever means in a position Where the separable contact means is locked open while the circuit to the electroresponsive means is also open, and in a further selected manual setting closing the circuit to the electroresponsive means while permitting free movement of the lever means under the control of the electroresponsive means to open and close the separable contact means.

13. Switching apparatus `comprising in combination, separable contact means, toggle means operatively connected to the separable contact means, the separable contact means being closed when the toggle means is at a near toggle point, the separable contact means being open when the toggle means is away from said near toggle lpoint by at least a predetermined amount, electroresponsive means including a solenoid having a rotatable armature, said armature being operatively connected to the toggle means for controlling the position of the toggle means to thereby control the separable contact means, and spring means operatively connected to the toggle means for automatically moving the toggle means away from the near toggle point by at least said predetermined amount when an energizing potential is removed from the electroresponsive means.

M. Switching apparatus comprising in combination, separable contact means, toggle means operative connected to theV separable contact means, the separable contact means being closed when the toggle means is at a near toggle point, the separable contact means being open when the toggle means is away from said near toggle point by at least a predetermined amount, and electroresponsive means including a solenoid having a rotatable armature, said armature being operatively connected to the toggle means for controlling the position of the toggle means to thereby control the separable contact means, the solenoid and separable contact means being so mounted that the force of gravity acting on the rotatable armature and on lat least a portion of the separable contact means opens the Contact means when the solenoid is deenergized.

t5. Switching apparatus comprising in combinationr separable contact means, toggle means operatively connected to the separable contact means, the separable contact means being closed when the toggle means is at a near toggle point, the separable contact means being open when the toggie means is away from said near toggle point by at least a predetermined amount, electroresponsive means including a solenoid having a rotatable armature, said armature being operatively connected to the toggle means for controlling the position of the toggle means to thereby control the separable contact means, and manually operable means for selectively locking the toggle means at the near toggle point and away from the near toggle point by said predetermined amount to selectively lock the separable contacts in closed and open positions and at the same time prevent the energization of the electroresponsive means.

References Cited by the Examiner UNITED STATES PATENTS 1,142,852 6/1915 Simon 200-87 X 1,763,502 6/1930 Branchu. 2,001,897 5/1935 West et al. 20G-94 X 3,016,435 l/l962 Schwartz 20G- 94 BERNARD A. GILHEANY, Primary Examiner.

T. MACBLAIN, R. N. ENVALL JR.,

Assistant Examiners.

Claims

1. SWITCH APPARATUS COMPRISING, IN COMBINATION, FIXED CONTACT MEANS, MOVABLE CONTACT MEANS MOVABLE INTO ENGAGEMENT WITH THE FIXED CONTACT MEANS TO CLOSED THE SWITCH AND MOVABLE OUT OF ENGAGEMENT WITH SAID FIXED CONTACT MEANS TO OPEN THE SWITCH, OPERATING MEANS INCLUDING A TOGGLE MECHANISM FOR EFFECTING MOVEMENT OF THE MOVABLE CONTACT MEANS INTO ENGAGEMENT WITH THE FIXED CONTACT MEANS WHEN THE TOGGLE MECHANISM IS MOVED AT LEAST TO A NEAR TOGGLE POINT AND OUT OF ENGAGEMENT WITH THE FIXED CONTACT MEANS WHEN THE TOGGLE MECHANISM IS MOVED AWAY FROM THE TOGGLE POINT BY AT LEAST A PREDETERMINED AMOUNT, SOLENOID ACTUATED MEANS INCLUDING A SOLENOID HAVING A ROTATABLE ARMATURE AND A ROTATABLE SHAFT SECURED THERETO FOR ROTATION THEREWITH, LINK MEANS OPERATIVELY CONNECTING THE TOGGLE MECHANISM TO THE ROTATABLE SHAFT FOR MOVING THE TOGGLE MECHANISM AT LEAST TO SAID NEAR TOGGLE POINT WHEN THE SOLENOID IS ENERGIZED TO EFFECT A CLOSING OF THE SWITCH, AND SPRING MEANS OPERATIVELY CONNECTED TO THE SOLENOID ACTUATED MEANS AND INCLUDING A SPRING NORMALLY TENSIONED TO A FIRST DEGREE WHILE THE SOLENOID IS DEENERGIZED, SAID SPRING BEING TENSIONED TO A SECOND DEGREE GREATER THAN SAID FIRST DEGREE WHEN THE SOLENOID IS ENERGIZED, SAID SPRING WHEN THE SOLENOID IS THEREAFTER DEENERGIZED CAUSING THE TOGGLE MECHANISM TO MOVE AWAY FROM THE NEAR TOGGLE POINT BY SAID PREDETERMINED AMOUNT AND OPEN SAID SWITCH.