US3222476A

US3222476A - Electromagnetic switch

Info

Publication number: US3222476A
Application number: US302591A
Authority: US
Inventors: Harold E Whiting; Jordan F Puetz
Original assignee: Square D Co
Current assignee: Schneider Electric USA Inc
Priority date: 1963-08-16
Filing date: 1963-08-16
Publication date: 1965-12-07
Anticipated expiration: 1982-12-07

Description

1965 H. E. WHITING ETAL 3,222,475

ELECTROMAGNETIC SWITCH 2 Sheets-Sheet 1 Filed Aug. 16 1963 IN VEN TOR. HAROLD E WH/ TING (JORDAN F PUETZ BY c- 1965 H. E. WHITING ETAL 3,222,476

ELECTROMAGNETIC SWITCH Filed Aug. 16, 1963 2 Sheets-Sheet 2 k 4s 74 70 74 4a 70 4s 74 70 74 4s "I 26. 3 24 x I l I! I, -\I--| WM INVENTOR HAROLD E. WH/T/NG JORDAN F. PUETZ United States Patent 3,222,476 ELECTROMAGNETIC SWITCH Harold E. Whiting, Bayside, Milwaukee, and Jordan F.

Puetz, Milwaukee, Wis., assignors t0 Square D Company, Park Ridge, Ill., a corporation of Michigan Filed Aug. 16, 1963, Ser. No. 302,591 9 Claims. (Cl. 200-104) The present invention relates to electrical switching devices and is more particularly concerned with a novel arrangement and construction of the parts of an electromagnetic switching device which will provide an economical and reliable switching device which can be serviced with minimum difficulty.

Electromagnetic switching devices usually are provided with a magnet motor which includes a stationary magnet part, a coil and an armature which is moved in response to magnet flux induced in the stationary magnet and armature by current flow through the coil. The armature frequently is connected to a yoke which carries a plurality of movable contact-s which are arranged to move relative to a plurality of stationary contacts to either a circuit closing or a current opening position upon movement of the armature.

The electromagnetic device according to the present invention is provided with a base which supports the stationary contacts of the device with the stationary contacts being arranged as a plurality of pairs of contacts, each pair being separated by partitions to provide adequate electrical clearance and arc isolation between adjacent pairs of contacts. The device also includes an assembly which comprises a magnet motor and a yoke which carries the movable contacts of the device. The yoke is arranged to be guided by portions of a cover for the device so the movable contacts will be properly guided as they engage the stationary contacts.

It is an object of the present invention to provide an electric switching device with a base which has a plurality of pairs of spaced stationary contacts oriented as pairs in parallel rows and with insulating partitions separating the respective pairs from each other and to provide the device with a movable contact assembly which includes a plurality of pairs of movable contacts which are arranged to be moved into engagement with the stationary contacts upon energization of a magnet motor which is part of the assembly and which is positioned on the base by a cover which encloses the assembly and is arranged to guide the movable contacts into engagement with the stationary contacts.

It is another object of the present invention to provide a cover for electric switching device with means for positioning a coil of an electromagnet operator for the device on a base for the device and a means for guiding the movable contacts of the device into engagement with stationary contacts which are carried by the base.

In carrying out the above object it is another object of the present invention to secure the cover to the base and the coil to the base by a pair of screws which engage a pair of U-shaped threaded members carried by the base.

A further object of the present invention is to provide an electric switching device with a base which positions a plurality of pairs of stationary contacts, a movable contact assembly which includes a magnet motor and a plurality of movable contacts which are arranged to be moved into and from engagement with the stationary contacts by the magnet motor, and a cover which is secured to the base and encloses the movable contact assembly with an arrangement whereby slots in the end walls of the cover provide a guiding means for lugs on the ends of a yoke which carries the movable contacts of the switching device so the movable contacts are guided 3,222,476 Patented Dec. 7, 1965 ice into engagement with the stationary contacts and an arrangement whereby an armature of the magnet motor is secured to the yoke by a spring clip which is arranged to permit movement of the armature so proper engagement will occur between the pole faces of the armature and a stationary magnet part of the magnet motor when a coil of the magnet motor is energized.

In carrying out the foregoing object it is another object to form the yoke as a U-shaped part which has the movable contacts resiliently carried on the bight portion of the part and wherein a pair of arms of the part extend from the bight portion on opposite sides of the coil and stationary magnet and wherein each of the arms is provided with an elongate opening to receive a spring for resiliently supporting the yoke on the base of the device and wherein each of the arms is provided with a support for the armature and a cylindrical end for receiving socket-like arms of the clip which movably secures the armature to the yoke.

Further objects and features of the invention will be readily apparent to those skilled in the art from the specification and appended drawing illustrating certain preferred embodiments in which:

FIG. 1 is a top plan view of an electric switch incorporating the features of the present invention.

FIG. 2 is a sectional view taken along line 22 in FIG. 1.

FIG. 3 is an exploded end view of the switch in FIG. 1.

FIG. 4 is an exploded side view of the switch in FIG. 1.

In the drawings, a switching device 10 is provided with a base 12, a movable contact assembly 14, and a cover 16. The base 12, which is preferably formed of a suitable molded insulating material, may be secured to a member 18 by threaded screws 20. The member 18 is provided for purposes of securing the switching device 10 to a suitable panel or other support.

The base 12 is provided with a central cavity which is divided by a plurality of parallel spaced partitions 22, one of which is shown partly in section in FIG. 4. The partitions 22, each of which is provided with a central notch 36, are arranged to divide the cavity within the base into a plurality of spaced compartments, each of which has a pair of spaced stationary contacts 24 located therein. The stationary contacts 24 are each electrically connected with a terminal member 26 which are arranged to receive and secure a bared end of an electrical conductor. The terminal members 26 are located on the base external of the cover 16 when the cover 16 is applied to the base 12 in the manner which will be hereinafter described. The partitions 22 separate the stationary contacts into parallel rows of stationary contacts as apparent from FIGS. 2 and 4 of the drawings. The base 12 is also provided with a pair of bosses 28 which are located on the base as shown in FIGS. 2 and 4 of the drawings. The bosses 28 are arranged to receive a U- shaped clip 30. A bight portion 30a of the U-shaped clip has a pair of arms 3% and 300 extending therefrom. The arm 30b is provided with a barb which is received in a recess in the boss 28 so as to anchor the clip 30 on the boss 28. The arm portion 300 is provided with a threaded opening 30d aligned with an opening 32 in the boss 28 to receive the threads of a screw 34, as will be hereinafter described.

The movable contact assembly 14 includes a magnet motor 38 having a stationary magnet part 40, a coil 42 and an armature 44. The assembly 14 also includes a yoke 46 which is preferably formed of a molded insulating material to carry a plurality of spaced movable contacts 48. The yoke 46 and armature 44 are removably ecured to each other by means of a spring clip 50, which will be hereinafter described. The coil 42 is preferably molded to have a slot 52 extending along its bottom surface to embrace a bight portion 54 of the stationary magnet part 40. The coil 42 also has a pair of outwardly extending lugs 56 arranged to rest on the upwardly extending portions 28 of the base 12 when the device is assembled. The lugs 56 are provided with suitably located apertures 42a to receive the screws 34 when the cover 16 is secured to the base 12 in the manner which will be hereinafter described. Each of the lugs 56 has a terminal 58 which is electrically connected to an end of the coil Winding and is arranged to be connected to a bared end of an electrical conductor. The coil 42 is provided with a rectangular central opening extending therethrough which receives a central leg of the stationary magnet part 40 and a central leg 60 of the armature 44. The stationary magnet part 40 and the armature 38 are both E-shaped and each have outer legs 62, 64, respectively, providing pole faces which are engageable with one another when the coil 42 is energized. The outer legs 62 and 64 are disposed exterior to the coil 42 and are received between a pair of arm portions 68 of the yoke 46. The yoke 46 has a bight portion 66 connecting the arm portions 68 which is provided with a plurality of spaced slots 70 that are arranged to pass in the notches 36 and straddle the partitions 22 in the base 12. The notches 70 separate the bight portion 66 into a plurality of spaced movable contact supports which are arranged to extend downwardly into the compartments wherein the stationary contacts 24 are disposed. The movable contact supports are suitably apertured to receive the movable contacts 48 and a spring 74 which resiliently biases the movable contacts 48 downwardly as in FIG. 4. Extending inwardly from each of the free ends of arm 68 is a ledge 76 which has its top surface slightly rounded and arranged to engage a portion 78 of the armature. Extending upwardly from the ledge portion 76 on the free end of each of the arms 68 is a knob 80 which is centered axially with the top of the rounded surface of ledge 76. The knobs 80 each are arranged to receive a pair of curved arms which form a pair of sockets 82 which extend downwardly from the opposite ends of the clip 50. Positioned intermediate the sockets 82 and extending in the same direction as the arms which provide the sockets 82 are a pair of arms 84 which are arranged to tightly receive the external surfaces on opposite sides of the center of the armature 38 so as to secure the clip 50 to the armature 44. Each of the arms 68 of the yoke 46 has an outwardly Vertically extending lug 86 ertending in opposite directions. The lugs 86 are received in suitably located slots 89 in the cover 16.

The arms 68 also have vertically extending openings 88. A spring 90 which is positioned in each of the openings 88 has one end seated on a seat 92 at one end of the openings 88 and engages a member 94 at the other end of the openings 88. The springs 90 urge the members 94 into engagement with an insulating member 96. The ends of the insulating member 96 are suitably notched to embrace the arms 68 as the midportion of member 96 rests upon the bight portion 66, of the yoke 46. The notched end portions of the insulating member 96 are arranged to rest upon ledges at the opposite end surfaces of the cavity within the base 12 so as to resiliently support the yoke on the base when the base and yoke are assem bled. A rubber-like strip member 98 is positioned between the stationary magnet part 40 and the member 96.

The cover 12 is preferably formed of a suitable molded material and has a pair of openings 16a which are located to receive the screw 34 for securing the cover 16 to the base 12. The cover is provided with notches 99 which receive the bosses 28 on the base 12 and an opening 160 which will permit observation of the armature 44 when the parts are assembled to determine whether or not the device is in the energized or de-energized condition. Preferably, one of the walls of the slots 89 in the cover 12 is covered with a metal surface 102, so that the lugs 86 which are formed of insulating material, will engage a metal surface and minimize wear of the device in service.

In view of the foregoing description, the assembly of the device will be hereinafter set forth. The base 12, including the stationary contacts 24 which are connected to the terminal members 26 and the clips 30 which are secured in position on lugs 28, is secured to the member 18 by bolts 20. An assembly comprising the yoke 46, the movable contacts 48, the spring 74, the insulating member 96, the members 94 and springs 90, is assembled with the stationary magnet part 40 which has the resilient bumper 98 secured along the bottom surface and in engagement with the member 96. The coil 42 is then placed over the central lugs of the stationary magnet part with the slots 52 receiving the bight portion of the stationary magnet part 48. The clip 50 is also assembled with the armature 44 by inserting the center of the bight portion of the armature 44 between the spaced arms 84 of the clip 50. The assembly, including the clip 50 and armature 44, is then positioned on the yoke 46 by causing the resilient arms which provide the sockets 82 to engage the knobs on the yoke. When this connection is accomplished, the rounded surface provided by the ledges 76 and the rounded surface provided by the knobs 80 will permit the armature 44 to have a limited rocking motion relative to the yoke 46 so as to permit firm seating between the pole face of the armature 44 and the stationary magnet part 48 when the coil 42 is energized. The movable contact assembly 14, which includes the yoke 46, the coil 42, the stationary magnet part 40, the armature 44 and clip 56, is then assembled with the base 12. When the base and movable contact assembly are combined, the lugs 56 on the coil are positioned on the portions 28 of the base and the insulating member 94 rests upon ledge portions of the base to support the stationary magnet part on the base. After the base 12 and movable contact assembly 14 are thus assembled, the cover 16 is then positioned on the base 12 to completely enclose the movable contact assembly 14. The cover 16 and coil 42 are secured to the base by means of the screws 34 which extend through the openings 16a in the cover, the opening 42a in the lug 56 and the opening 32 in the boss 28 into the threaded openings 30d of the clip 30. When the cover 16 is thus secured, the slots 89 will receive lugs 86 and act as a guide means to vertically guide the yoke 46 of the movable contact assembly 14 when the magnet motor is energized to move the movable contacts 48 into bridging engagement with the pairs of spaced stationary contacts 24 on the base 12.

While certain preferred embodiments of the invention have been specifically disclosed, it is understood that the invention is not limited thereto, as many variations will be readily apparent to those skilled in the art and the invention is to be given its broadest possible interpretation within the terms of the following claims:

What is claimed is:

1. In an electric switching device, an insulating base having a plurality of pairs of spaced stationary contacts oriented as pairs in parallel rows on the base and insulating partitions separating each of said pairs from an adjacent pair of stationary contacts, a movable contact assembly including movable contacts and a magnet motor removable as a unit from the base and a cover enclosing the movable contact assembly and having portions engaging with portions of the magnet motor positioning the magnet motor on the base and slots engaging portions of the movable contact assembly guiding the movable contacts of said assembly into engagement with the stationary contacts.

2. The combination as recited in claim 1 wherein the movable contact assembly includes a yoke formed of insulating material having spaced openings positioning a plurality of movable contacts which are spaced and oriented to bridgingly engage the pairs of stationary contacts on the base, and the portions of magnet motor engaged by the cover are provided by oppositely extending terminal portions on a magnet coil which are held in position on a portion of the base by the cover.

3. The combination as recited in claim 2 wherein the yoke includes a pair of lugs extending in opposite directions which are received in the slots in the cover for guiding the movable contacts into engagement with the stationary contacts.

4. The combination as recited in claim 1 wherein the magnet motor includes: an E-shaped stationary magnet, a coil having a central opening receiving a central leg of the E-shaped stationary magnet and immovably positioning the stationary magnet on the base when the coil is secured to the base, an E-shaped armature having an inner leg received within the opening of the coil and a pair of outer legs arranged to engage a pair of outer legs of the stationary magnet upon energization of the coil, an elongate carrier having; a plurality of openings positioning the movable contacts, a pair of guides extending in opposite directions movable in the slots in the cover and means including a pair of spaced rounded ledges supporting the armature on the carrier and a spring clip engaging the armature and carrier for maintaining the armature on the rounded ledges.

5. The combination as recited in claim 4 wherein the carrier has a pair of spaced rounded lugs and the spring clip is provided with a pair of spaced resilient arms at each end of the clip for receiving the rounded lugs and a pair of spaced resilient arms intermediate its ends for resiliently securing the armature to the clip.

6. The combination as recited in claim 1 wherein a pair of U-shaped clips carried by the base have threaded openings for a pair of screws for securing the cover to the base.

7. In an electric switching device the combination comprising; an insulating base having opposed end walls, opposed side walls, a bottom wall and a plurality of spaced partitions extending between the bottom and side walls and parallel to the end walls providing a plurality of spaced compartments, a pair of spaced stationary contacts in each of said compartments spaced on opposite sides of a center line, a guide way in each of the end walls extending normal to the bottom wall along an axis extending through the center line, an insulating member having a pair of spaced parallel arms extending from an interconnecting bight portion, said arms being spaced for receipt in the guide ways for guiding movement of the bight portion along an axis normal to the bottom wall into juxtaposition with the bottom wall, a plurality of movable contacts carried by the bight portion and spaced to be received in the compartments and bridgingly engage the stationary contacts in the compartments when the insulating member and bottom wall are in juxtaposition, a ledge on a free end of each of the arms of the insulating member extending inwardly toward each other and having a rounded surface facing away from the bight portion, a knob on the free end of each arm of the insulating member, and a guide on the free end of each of the arms of the insulating member extending in opposite directions from each other, a resilient means operative between the base and arms for constantly urging the bight portion of the insulating member out of juxtaposition with the bottom wall, a magnet motor having an E-shaped stationary magnet supported on the base and received between the arms of the insulating member, a coil having a central opening for receiving a central leg of the E-shaped stationary magnet and an E- shaped armature having portions resting on the ledges of the arms of the insulating member and having an inner leg received within the opening of the coil and a pair of outer legs disposed external to the coil and arranged to engage a pair of outer legs of the stationary magnet upon energization of the coil, a resilient elongate clip having a pair of spaced resilient arms at each end embracing the knobs on the arms of the insulating member and a pair of spaced resilient arms intermediate the ends of the clip embracing the armature for resiliently and rockingly securing the armature to the insulating member, and a cover having a portion engageable with portions of the coil for positioning the coil on the base and a pair of slots receiving the guides on the arms of the insulating member for guiding the free ends of the arms of the insulating member during movement of the bight portion of the insulating member toward the base.

8. The combination as recited in claim 7 wherein the base is provided with a pair of U-shaped clips which are disposed on opposite sides of the base and are provided with threaded openings for receiving a threaded member extending through the cover and the coil portions for securing the cover and coil on the base.

9. In an electric switching device having stationary contacts, movable contacts and a magnet motor assembly for moving the movable contacts into engagement with the stationary contacts, said magnet motor assembly comprising; a U-shaped insulating member having a pair of spaced parallel arms extending from opposite ends of a bight portion, means for resiliently supporting the movable contacts on the bight portion, a ledge on an inner surface of a free end of each of said arms, a rounded surface on each of said ledges facing away from the bight portion and a knob on the free end extremity of each arm, a magnet motor having a coil, a stationary magnet part and an armature having portions engageable with the stationary magnet upon energization of the coil and portions resting on the rounded surface of the ledges, a resilient connection between the stationary magnet and the insulating member, and a spring clip providing a connection between the insulating member and armature, said clip having a pair of spaced arms located intermediate the ends of the clip embracing opposite sides of the armature providing an immovable connection between the clip and armature and a pair of spaced arms at each end of the clip arranged to provide a socket connection with the knobs on the ends of the arms of the insulating member whereby the armature is pivotally supported on the insulating member to permit the engaging portions of the armature to firmly seat on the stationary magnet upon energization of the coil.

References Cited by the Examiner UNITED STATES PATENTS 2,897,316 7/1959 Brauneck 200-104 2,924,685 2/1960 Burch ZOO-T04 3,042,774 7/ 1962 Hawkins 200104 BERNARD A. GILHEANY, Primary Examiner.

ROBERT K. SCHAEFER, Examiner.