US1931914A - Magnetically operated switch - Google Patents

Description

Oct. 24, 1933. Q Q w|| M$ uAGNETIcALLY OPERATED SWITCH Filed July 27. 1928 @MTM/s@ Patented Oct. 24, 1933 UNITED STATES MAGNETICALLY OPERATED SWITCH Gustav 0. Wilnis, Milwaukee, Wis., assignor, by mesne assignments, to Allen-Bradley Company, Milwaukee, Wis., a corporation of Wisconsin Application July 27. 1928. Serial No. 295,693

13 Claims.

This invention relates particularly to the actuating mechanism of electromagnetically operated switches.

Great difllculty has been experienced in the past in providing an A. C. switch which is capable of being held in closed position during voltage drops to comparatively low values, as for an example approximately 40% or :lower than the normal line voltage, and this invention has as an l0 object the provision of an improved switch structure which is so designed as to be substantially unaffected by line voltage drops thus preventing the opening of the switch under such variations in the line voltage.

Another object 'of this invention resides in the provision of an improved switch structure in which the armature is connected with the movable contacts by a toggle joint having the characteristic of increasing the force applied to the joint as the armature approaches the solenoid whereby the magnetic'force necessary to hold the armature and the contacts in is relatively small, thus precluding the possibility of the Switch opening during line voltage drops.

Another object of this invention resides in the provision of an improved switch structure whereby the retaining of the contacts in closed position without contact pressure thereon is eliminated to thus prevent fusing of the contacts.

Another object of this invention resides in the provision of an improved switch structure in which the armature is connected with the movable switch contacts through a toggle joint whereby a relatively small degree of magnetism is re- 35 quired to maintain the armature in, so that the voltage with which the switch is used readily maintains the armature quiet and the occurrence of comparatively large voltage drops does not release the armature. l

Heretofore the actuating mechanism of such switches has required extreme care and tedious tting of the armature with the core pole faces as the armature has been invariably pivoted at one end to a fixed support having its free end 45 attracted by the energization oi the solenoid.

This invention further contemplates an actuating mechanism in which the usual tedious hand work necessary to produce the exact fit between the pole faces and the armature is obviated.

Another object of this invention is to provide means for mounting the armature of the actuating mechanism so that it is free to align itself with the pole faces without resorting to the usual practice of loose tting mechanical joints.

A further object of this invention resides in the provision of an actuating mechanism for a switch of the character described in which the armature at all times maintains a position substantially parallel with respect to the pole faces 160 of the core.

(Cl. 20D-87) And a further object of this invention resides in the provision of an electro-magnetically operated switch having a substantially E-shaped core, around the center arm of which a solenoid is wound.

With the above and other objects in View which will appear as the description proceeds, my invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claims, it beingY understood that such changes in the precise embodiment of the herein disclosed invention may be made as come within the scope of the claims.

In the accompanying drawing, I have illustrated one complete example of the physical embodiment of my invention constructed according` to the best mode I have so far devised for the practical application of the principles thereof, and in which:

Figure l is an end view of an electrical unit embodying my invention, parts thereof being broken away and in section; and

Figure 2 is a front plan view thereof, a part of the armature being broken away.

Referring now more particularly to the accompanying drawing, in which like numerals designate like parts throughout the several views, 5 represents a panel of suitable insulating material upon which a plurality of stationary contacts 6 are mounted to be connected with an electric circuit, not shown, by conductors 7. Movable switch arms 8 secured to a carrying member 9 by screws l0 and having conductors 11 suitably connected therewith, as at 12, are moved in unison to engage the contacts 6 and close the circuit, not shown.

The carrying member 9 is preferably formed of insulating material and is pivotally mounted at one end from a bracket member 13 secured to the panel and having an outwardly extended arm 14 which is apertured to receive a stud 15 riveted or otherwise secured thereto, the stud being freely pivotally received in an aperture 16 of a projection 17 on member r9. The opposite end of the carrying member 9 is reduced in width and has an inwardly projected arm or extension 18 through which an aperture extends in axial alignment with the stud 15. The inwardly projected arm is received between ears or lugs 19 extended from side pieces 20 forming the frame of the actuating mechanism, and is pivotally connected therewith by a stud 2l passing through the aperture in the arm 18 and aligned apertures in the ends of the ears or lugs 19.

The actuating mechanism includes a laminated core 22 of substantially E shape, as illustrated in Figure l, the laminations being confined between the side pieces 20 by rivets or other means 23 The side pieces 20 have laterally extended flanges 24 by which the core is mounted on the panel by bolts 25, and their major portionsconform to the E shape of the core. The ends of the side pieces each have a part directed outwardly, as at 20', and then lateralLv to form the ears 19 at the lower ends and similar ears 26 at` their upper ends, for a purpose to be later described, the ears 19 being extended beyond the ears 26.

The outer arms of the E shaped core are maehined to lie in the same plane and provide the outer pole faces of two adjacent magnetic circuits with which the ends of an armature 28 are engageable and the center arm which terminates short of the plane of the outer arms forms a common pole for both magnetic circuits being at all times spaced from the armature to provide the necessary air gap, a solenoid 27 which, when energized, attracts the armature 28 to actuate the mechanism and move the member 9 to close the switch being mounted on the center arm. The armature is likewise preferably laminated having studs 29 and 30 tieing the laminations together and providing means for pivotally connecting pairs of lever arms 31 and 32 with the armature, the arms of each pair being positioned one on each side of the amature to movably mount the same.

The arms 31 forming the upper pair have their outer ends pivotally connected with the ears 26 by a pivot rod 33 and the arms 32 or the lower pair have their outer ends pivotaily connected with the outer end of the projection 18 formed on the member 9 by a pin 34.

This manner of mounting thel amature substantially diminishes the bang which usually accompanies magnetically operated switches of this type and further provides a greater mechanical advantage in closing the switch as the levers act substantially as a toggle ioint the Divot 33 being stationary, the movement of the amature upon attraction of the solenoid increasing the distance between the pivots 33 and 34 and straightening the levers 31 and 32 to impart a relatively great closing force to the switch arms 8 which builds up as the armature goes home".

When the solenoid is deenergized, the tension of the spring contacts start the opening movement tilting the member 9 about its pivotal mounting and raising the end of the projection 18 to decrease the distance between its outer end and the pivot 33 thereby moving the armature away from the pole faces to a position depicted by dotted lines in Figure 1. As the pivots 33 and 34 are inward of the pivots 29 and 30 when the switch is closed, the-mechanism at no time locks itself on dead center.

It will be noted that the annature is substantially free to adjust itself as it goes home and that this substantially floating mounting does not resort to objectionable loose joints between the moving parts of the mechanism. The perfect seating of the armature on the outer pole facesthus obtained cooperates with shading coils 35 to insure quietness.

From the foregoing description, taken in connection with the accompanying drawing, it will be readily apparent to those skilled in the art to which an invention of the character described appertains, that 1 have providedy an improved electro-magnetically actuated switch which employs a novel core, imparts a comparatively great closing force to the movable switch contacts at a relatively small voltage, and in which extreme care in fitting the parts to permit the armature to perfectly seat itself is obviated and one in which the amature is substantially free to adjust ltself to the core without resorting to loose joints between the moving parts.

What I claim as my invention is:

1. In an electromagnetically operated switch, a core having pole pieces, an armature movable to engage the pole pieces, a solenoid adapted upon energization to magnetize the pole pieces and attract the armature, a member movable to close and open the switch, a fixed support at a dis tance from said movable member, and a toggle joint connection including the armature as a part thereof between the fixed support and the movable member, movement of the armature toward the pole pieces straightening the toggle joint connection to increase the distance between the xed support and the point of connection of the movable member with the toggle joint to impart movement to said movable member.

2. In an electro-magnetically operated switch, a core having a pair of pole pieces with their end faces in substantially the same plane, a solenoid for magnetizing the pole pieces, mounting members extended from the core, a switch arm carrying member, means pivotally mounting the switch arms carrying member from one of the mounting members extended from the core, an armature, and levers connected with the armature, the other mounting member extended from the core and the switch arm carrying member, to mount the armature and form a toggle which is straightened to actuate the switch arm carrying member upon energization of the solenoid and the attraction of the armature thereto.

3. In an electro-magnetically operated switch including a movable contacter adapted to be magnetically held in its in position, a core having a pole piece, an4 armature adapted to be attracted to said pole piece to hold said movable contacter in its in position, a solenoid adapted upon energization to magnetize the pole piece and attract the armature thereto, and levers connected with the fixed support, the contactor and the armature and cooperating with the armature to form a toggle joint between the fixed support and the contactor so that the force applied to the movable contactor increases by the straightening of the toggle as the armature approaches the pole piece whereby the contacter is maintained in its in position during weakening of the magnetism of the pole piece to a predetermined degree below normal.

4. In an electromagnetically operated switch including an electromagnet, an armature adapted to be attracted thereto and a switch actuating member adapted to move in accordance with the armature, a fixed pivot about which the switch actuating member moves, a iixed support spaced from the fixed pivot, and levers connected with the xed support, the switch actuating member and the armature, said levers forming the sole support for the armature and with the armature forming a toggle joint connection between the iixed support and the switch actuating member, said toggle joint connection straightening as the armature moves toward the electromagnet to increase` the distance between the xed support and the point of connection between the switch actuating member and the adjacent lever to impart movement to the switch actuating member.

5. In combination with an electromagnet and an armature adapted to be moved upon energization of the magnet, a member to be moved by the armature, means movably mounting said member adjacent one end of the armature, a

nxed support adjacent the other end of the armature, and levers connecting the amature with the fixed support and the member to be moved whereby the levers and armature form a toggle joint connection between the fixed support and the member to be moved, which straightens out and increases the distance between the iixed support and the point of connection of the member to be moved with the adjacent lever as the armature moves toward the electromagnet to impart motion to the member to be moved.

6. In combination with an electromagnet and an amature movable upon energization of the magnet, a member to be moved, xed means pivotally mounting said member adjacent one end of the armature, a iixed support adjacent the other end of the armature, lever means connecting the amature with the fixed support and the member to be moved at a distance from its pivotal mounting, said lever means forming the sole support for the armature and with the armature forming a toggle joint connection between the fixed support and the member to be moved, which straightens out as the armature is attracted toward the electromagnet to increase the distance between the fixed support and the point of connection oi' the lever means with the member to be moved, whereby said member is rocked about its pivotal mounting.

'1. In an electromagnetically operated switch, an electromagnet having a substantially E shaped core, the ends of the outer arms of which are disposed in a common plane and form pole pieces. an armature adapted to be attracted to said pole pieces, and held in intimate engagement therewith upon energization of the electromagnet, a switch actuating member to be moved by the armature, means carried by one outer arm of the E shaped core for pivotally mounting said member, a xed support carried by the other outer arm of the core, and levers connecting the armature with said fixed support and the pivotally mounted switch actuating member, whereby said levers and armature form a toggle joint connection between the fixed support and the switch actuating member.

8. In an electromagnetically operated switch including an electromagnet, an armature adapted to be attracted thereto and a switch actuating member to be moved by the amature, a fixed pivot about which the switch actuating member moves, a fixed support spaced from the iixed pivot, a toggle joint connection between the xed support and the switch actuating member whereby straightening of th'e toggle connection moves the switch actuating member, and means connecting the armature with said toggle joint connection, whereby the armature is supported by the toggle joint connection between the fixed support and the switch actuating member and movement of the armature toward the electrol magnet straightens the toggle joint connection.

9. In a device of the character described, an electromagnet including a core having spaced pole pieces whose faces lie in a common plane, an armature adapted to be attracted to and held in intimate engagement with the faces o1' the lever means pivotally connected with the armature and said supports, said lever means with the armature forming a toggle joint connection adapted to straighten out upon attraction of the armature to the pole pieces to increase the distance between the xed support and the connection of the lever means with the movable support and impart movement to said movable support, and switch means operable by movement of said movable support.

10. In a device of the character described, a switch includingstationary contacts and movable contactors, a pivoted member carrying the movable contactors to swing them in an arc, an electromagnet at one side of the switch, said magnet being of a size substantially equal to the switch and including an armature movable upon energization of the magnet, a nxed support and lever means connected with the armature, the fixed support and the pivoted member carrying the movable contactors to form atoggle adapted to be straightened by the movement of the armature upon energization of the solenoid, straightening of the armature swinging the pivoted member to close the switch.

l1. In an electromagnetically operated switch, switch elements and an electromagnet disposed side by side, an armature adapted to be moved upon energization of the magnet, and a toggle connection including the armature as a part thereof for imparting movement of the armature to certain of the switch elements to close the switch.

12. In an electromagnetically operated switch including an electromagnet, a pivoted switch actuating member having an arm extending radially from the axis of its pivotal mounting, a fixed support opposite said arm, a link firmly pivoted to said iixed support, a second link rmly pivoted at one end to the arm of the switch actu- 11 ating member, and an armature rmly pivotally connected to the outer free ends oi' said links, whereby said links connected by the armature form a toggle joint connection between the fixed support and said arm of the switch actuating member, said armature being attractable to the electromagnet to straighten the toggle joint connection and swing the actuating member about its pivotal mounting with great force.

13. In an electromagnetically operated switch including an electromagnet having pole pieces, a switch actuating member pivotally mounted beneath the pole pieces, an arm carried by said switch actuating member and extending radially from the axis oi' its pivotal mounting, a fixed support above the pole pieces in line with said arm, a link firmly pivoted to the xed support, a second link firmly pivoted to said arm, and an armature firmly pivoted to the outer free ends of said links to positively connect the free ends of the links and form a toggle joint connection between the xed support and the arm oi' said actuating member, said armature being attractable to the pole pieces to straighten the toggle joint connection and impart movement to the actuating member and moving outwardly and upwardly with respect to the pole pieces upon deenergization o! the electromagnet to counterbalance the weight of the switch actuating member and its associated mechanism.

GUS'I'AV 0. WILMS.

CERTIFICATE OF CORRECTION` Patent No. 1,931,914. October 24, 1933.

GUSTAV 0. WILMS.

It is hereby certified that error appears'in the printed specification of the above numbered patent requiring correction es followsz- Page 2. line 117, claim 3, before "an second occurrence insert the words a fixed spport; and that the nid Letters Patent should be read with this correction therein that the same may conform to the record of the cue in the Patent Office.

Signed and seated thin 5th day of December, A. D. 1933.

i?. M. Hopkins (Seal) Acting Commissioner of Patents.

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