US2977438A - Relay-contactor - Google Patents

Description

March 28, 1961 Filed June 29, 1959 F. MORSCHEL RELAY-CONTACTOR 3 Sheets-Sheet 1 March 28, 1961 F. MORSCHEL RELAY-CONTACTOR 3 Sheets-Sheet 2 Flled June 29 1959 March 28, 1961 F. MORSCHEL 2,977,438

RELAY-CONTACTOR Filed June 29, 1959 3 Sheets-Sheet 3 I I I I I I A zz United States Patent RELAY-CONTACTOR Franz Morschel, Noereth 150, Eupen, Belgium Filed June 29, 1959, Ser. No. 823,653

9 Claims. (Cl. 200-87) The present invention relates to relay-contactors, the term being herein used in a generic sense to include circuit breakers, switches and other instrumentalities for opening and closing electrical circuits.

It is an object of the present invention to provide a relay-contactor which is wholly reliable in its operation and will give many years of service without failure or attention.

Another object of the invention is to provide a relaycontactor which is assembled without screws, rivets or similar fastening means except for means securing the cover on a case which houses operating mechanism of the relay-contactor. The virtual elimination of fastening means such as screws and rivets not only facilitates manufacture and assembly of the device but also contributes to providing years of trouble-free service by avoiding failures'attributable to the failure or loosening of such fastening means.

With relay-contactors heretofore available, the shock incident to repeated operation has caused a gradual but progressive deterioration limiting the useful life of the device. A further object of the invention is to avoid such deleterious effects and thereby greatly increase the useful life of the relay-contactor. For example a relaycontactor in accordance with the invention will operate satisfactorily as many as 50 million times.

The nature, objects and advantages of the invention will be more fully understood from the following description and claims in conjunction with the following drawings in which a preferred embodiment of the invention is shown by way of example.

In the drawings:

Fig. 1 is a front view of a relay-contactor in accordance with the invention.

Fig. 2 is an enlarged vertical section taken approximately on the line 2-2 in Fig. 1.

Fig. 3 is a horizontal section taken approximately on the line 3-3 in Fig. 1.

Fig. 4 is a perspective viewof an auxiliary contact unit.

Fig. 5 is a vertical section corresponding approximately to Fig. 2 but showing modifications.

Fig. 6 is a view taken approximately on the line 66 in Fig. 5 with the cover removed from the case of the device.

The relay-contactor shown by way of example in Figs. 1 to 4 of the drawings has a.case 1 which is conveniently molded of plastic material which is strong, durable and dimensionally stable. For example the case may be molded of a phenolic resin material. The case 1 is 2,977,438 Patented Mar. 28, 1961 ice shown .as comprising a base portion 2 and four sides,

3, 4, 5 and 6. At diagonally opposite corners adjacent the base, the case is provided with apertured lugs 7 to receive bolts, screws or other suitable fastening means for securing the relay-contactor on a vertical panel or other support with the base 2 disposed substantially in a vertical plane. The case 1 is provided with a cover 10 which fits onto the case and is suitably secured in place. In the form of the invention illustrated in Figs. 1, 2 and 3, the cover is held by diagonally opposite screws 11 extending through holes on the cover and screwed into lugs 12 provided on opposite sides 3 and 5 of the case. The lugs 12 have threaded holes to receive the screws 11. The cover is likewise preferably molded of plastic material and panel portion 13 and a plurality of partitions that project outwardly from the panel to form a plurality of separate cells. As illustrated in the drawings, the partitions comprise spaced parallel partitions 14 which are disposed equidistantly from a plane bisecting the cover and five vertical partitions 15 which intersect the horizontal partitions 14 to form separate cells 16. While the cover is shown in the drawing as having four such cells, it will be understood that more of fewer may be provided according to the number of contacts the relaycontactor is desired to have.

A plurality of stationary contacts are mounted on the panel portion 13 inside the cells 16 defined by the partitions 14 and 15. In the form of relay-contactor illustrated in the drawings, a pair of spaced stationary contacts 17 is provided in each cell. Each of the contacts comprises a strip or bar which is slipped through a slit at the base of the partition 14 and rests on the panel portion 13. A small projection or flange 18 on the panel 13 limits the distance the contact strip 17 can he slipped in. The dimensions of the parts are such that the contact strip 17 slips into place with a tight frictional fit so that it is held securely in place by friction. Near its outer end, the strip 17 is provided with a threaded hole to receive a screw 19 for securing a lead wire or other conductor to the contact strip. The cover is provided with holes 20 to receive the inner end portions of the screws 19. The holes 20 are not threaded as the screws 19 are for attaching conductors to the contact strips and not for mounting the contact strips on the cover. As described above, the contact strips are held in place by a tight frictional fit in the slots provided for them. How ever, when the screws '19 are in place, they hold the contact strips 17 from being pulled out of their respective slots, for example by a pull on the conductor, and hence provide double security. The vertical partitions 15 are preferably extended as indicated at 21 to provide separators isolating the outer ends of the contact bar 17 from one another and thereby avoiding any accidental short circuit between wires connected to the respective stationary contacts.

Movable contacts 22 provided in the cells 16 cooperate with the stationary contacts 17. As illustrated in the drawings, each of the movable contact members 22 comprises a bar having contact areas provided at its opposite ends and adapted to move between a closed position in which opposite end portions of the movable contact bar engage the two stationary contacts of a pair disposed in a cell 16 and an open position in which the stationary and movable contacts are disengaged from one another.

All of the movable contacts are carried and actuated by an actuating member 23 which is conveniently molded of plastic material for example a phenolic resin. The actuating member is shown as comprising a base portion 24 disposed inside the case 1 and a plurality of posts 25 extending out through openings in the cover into the cells 16, there being a post for each cell. At its outer end, each of the posts 25 is provided with diametrically opposite projecting portions which fit into an elongated opening in the central portion of the respective contact bar 22.. The contact bar is resiliently held in place by a key 26 which locks into the post 25 by being inserted through a slot and given a 90 turn and a compression spring 27 which acts between the key 26 and the bar 22.

The actuating member 23 is movable in a direction perpendicular to the cover by an electromagnet 30 housed in the case 1, The electromagnet comprises a coil or winding 31 and two core sections 32 and 33. The coil 31 is wound on a coil form 34 which is conveniently molded of plastic material. The coil form 34 is shown provided with an integral terminal board portion 35 carrying two terminals 36 for connecting the coil 31 to an energizing circuit. The assembly comprising the coil form 34 and coil 31 slips freely but snugly into the case 1, with the terminal board portion 35 fitting into a recess provided at the forward portion of the bottom of the case. The terminals 36 thus project downwardly from the case.

For convenience of manufacture, the two core sections 32 and 33 are alike, each consisting of a plurality of laminae of magnetically permeable material. As seen in Fig. 3 each of the core sections is E-shaped with a central portion 37 received inside the coil 31 and opposite side portions 38 which together provide a magnetic circuit surrounding the coil. The core sections are movable from a position in which they are separated from one another as shown in Figs. 2 and 3 to a position in which they are in engagement with one another. The front core section 3-3 is interlocked with the actuating member 23- by means of undercut portions 39 engaging complemental portions of the actuating member. The front core section and actuating member are thus dovetailed into one another and held without screws, rivets or similar fastening means.

Resilient means shown as oppositely disposed compression springs 49 act between the coil form 34 and the actuating member 33 to move the actuating member forwardly and thus separate the magnet core sections as shown in the drawings. When the coil 31 is energized by current supplied through the terminals 36, the coil sections 32 and 33 are attracted toward one another and the front coil section 33 and actuating member 23 are thereby drawn inwardly to bring the movable contacts 22 into engagement with the stationary contacts 17. The rear core section 32 rests against a block of foam or sponge material 41 positioned between internal flanges 42 on the base of the casing and held in position by adhesive or otherwise. The material 41 is foam rubber or other elastomer material having the properties of being relatively soft and compressible with sufficient elasticity to return to its original form when pressure is released. The block 4-1 is of sufficient thickness to be compressed a substantial amount between the rear core section 32 and the base of the case when the magnet is in position in the case and retained by the cover 10.

The parts of the relay-contactor in accordance with the invention are readily assembled without the use of any screws, bolts or other connecting means except for the screws 11 which secure the cover to the case 1. As described above, the stationary contacts 17 are assembled on the cover 10 merely by pushing them lengthwise into position. The front core section 33 and the actuating member 23 are assembled by slipping the actuating member in between the undercut dovetail portions 39 of the core section. The posts of the actuating member are slipped up through the corresponding holes in the cover and the movable contacts with their associated springs 27 are secured in place by the keys 26 which are inserted through slots provided in the ends of the posts 25 and then turned to lock them in place by a bayonet-type joint. The rear core section 32 is slipped onto the coil assembly and the coil is slipped into the case 1. The cover 10 is then put on carrying with it the front core section which fits down over and into the coil. The cover is secured in place by the two screws if to complete the assembly operation.

When the coil 3-1 is deenergized, the springs 40 hold the actuating member 23- in a forward position in which the movable and stationary contacts are separated as illustrated in Fig. 2. When the coil is energized, the two core sections are attracted toward one another. As the rear core section 32 is restrained from forward movement by the coil form 34 which in turn is held by the cover 10, the front core section 33 is drawn rearwardly, thereby bringing the movable contacts into engagement with the stationary contacts 22. The foam block 41 cushions any impact resulting from engagement of the forward core section 33 with the rear section 32. Moreover, the entire coil assembly comprising the coil form 43 and coil 31 can move a limited distance rearwardly, such movement being likewise cushioned bythe foam block 41. As the impact is thus cushioned and the energy of impact dissipated by the foam cushion, any destructive effect of such impact on the device is avoided or minimized. Moreover, since there are no internal screws or other securing means which can be loosened by repeated impact, the life expectancy of the relay-contactor in accordance with the invention is far greater than that of devices heretofore available.

A further feature of the invention is that the number of available contacts can be increased as desired by the use of one or more auxiliary contact units 50 fitting into one or more of the cells 16 of the cover. As illustrated in the drawings (Figs. 1 to 4) each auxiliary contact unit 50 comprises a body portion 51 which is conveniently molded of plastic insulating material. The body portion 51 is provided with four resilient finger portions 52 which fit snugly into the four corners respectively of one of the cells 16. A fifth finger 53 is provided at its end with a detent portion 54 adapted to engage a recess or other cooperating shoulder 55 to retain the auxiliary contact unit in the position shown in Figs. 2 and 3 by a releasable spring-catch action.

The auxiliary contact unit 50 is shown provided with a stationary contact 56 carried by a U-shaped metal clip 57 provided at its outer end with a terminal screw 62. The spring arm 60 is in position to be engaged by a key 26 of the actuating member 23 so that when the actuating member is in its forward position the movable contact 59 is held in engagement with the stationary contact 56. To isolate the contacts of the auxiliary contact unit from those of the main relay-contactor the key portion 26 is made of fiber or other insulating material or is provided with an insulating cap on its upper end. Alternatively a slidable plunger 63 extending out through a bore in the body portion 51 is operablemanual-ly to actuate the movable contact. In this case the contacts are normally closed and are opened by the plunger 63. It will thus be understood that the contacts may be normally open or normally closed as desired. It will further be understood that an auxiliary contact unit such as unit 50 may be inserted in any one or more of the cells 16 onthe cover 10 to increase the number of available contacts of the relay as desired. 7

Several modifications are illustrated in Figs. 5 and 6 where corresponding parts are designated by the same reference numerals as in Figs. 1 to 4. The relay-contactor is shown in mounted position on a vertical panel or other support 65 where it is held by screws 66. In the embodiment shown in Figs. 5 and 6, the resilient means for separating the core sections of the magnet comprise blocks 40a of resilient foam material which seat in sockets 67 on the coil form 34 and bear against an inner face of the actuating member 23. The foam material comprising the blocks 40a may be identical with or similar to the foam material of the block 41 disposed between the rear magnet core section and the base of the case. It is sufficiently compressible to permit the outer core section 33 to be drawn inwardly into engagement with the inner core section 32 when the coil of the electromagnet is energized. It is sufiiciently elastic to return to the position shown in Fig. 5 thereby separating the core sections and also separating the movable and stationary contacts when the coil is deenergized. The foam material has a long life and is not subject to crystallization or fatigue failure as is a metal spring.

In Fig. 5 the cover is shown held inplace on the case by spring clips 11a which fit over complemental lug portions of the cover and case. The clips are held securely in place by small detents 68 which snap into corresponding holes or recesses provided in the complemental lug portions of the case and cover. The spring clips 11a permit more rapid and economical assembly and are also preferable to screws or bolts in that they cannot work loose.

In Fig. 5 there is also shown an auxiliary contact unit 50a which is similar to the unit 50 shown in Figs. 1 to 4 except that the stationary contact 56a carried by the clip 57a and the movable contact 59a carried by the spring 60a are normally closed and are separated from one another as shown in Fig. 5 by the key 26 of the actuating member 23 when the latter is in its outer position.

Except for the differences shown and described, the relay-contactor shown in Figs. 5 and 6 is like that of Figs. 1 to 4 and operates in like manner.

It will be understood that the invention is in no way limited to the details of the preferred embodiments shown by way of example in the drawings and herein particularly described and that various other modifications may be made within the scope of the invention.

What I claim and desire to secure by Letters Patent is:

1. A relay-contactor comprising a case, an electromagnet in said case and comprising a winding coil and a core of magnetically permeable material, said core being divided into two complemental sections, namely a front section and a rear section, means positioning said coil in said casing, said core sections being movable relative to said coil, means limiting forward movement of said rear core section, cushioning means yieldably holding said lower core section in engagement with said limiting means, said cushioning means comprising a block of foam material under compression, at least one pair of cooperating electrical contacts comprising a movable contact and a stationary contact, means coupling said movable contact with said upper core section for movement thereby between one operative position in which said contacts are closed and another operative position in which said contacts are open, means biasing said front core section to a forward position in which said core sections are separated from one another and said movable contact is in one of said operative positions, and means for energizing said winding to draw said core sections together and thereby move said movable contact to the other of said positions, said foam material absorbing the energy of impact of said front core section with said rear core section.

2. A relay contactor as described in claim 1 characterized in that said means coupling said movable contact with said upper core section comprises an actuating member having means for mounting said movable contact, said actuating member having a lower portion defining an inner part of a dovetail joint, said upper core section having its top surface undercut to define a complementary outer part of said dovetail joint, and engaging said inner part of said dovetail joint to couple said movable contact mounted in said actuating member to said upper core section.

3. A relay contactor as described in claim 2 characterized in that said means for mounting said movable contact on said actuating member comprises on said actuating member a hollow post having a slotted top for supporting said movable contact, said movable contact having a hole coincident with said slotted top, a coiled spring for engaging said movable contact, a key having a spring retaining top, a spring engaging shank and oppositely disposed bottom projections, said bottom projections adapted to fit through said slotted top of said hollow post and rotate to lock in a bayonet type joint for securing said movable contact to said post of said actuating member.

4. A relay-contactor comprising a case having side walls, a base and a removable cover, an electromagnet in said case and comprising a coil and a core of magnetically permeable material, said core being divided into two complementary sections, namely a front section and a rear section, means positioning said coil in said case with its axis extending fore and aft, said core sections being movable relative to said coil, means limiting forward movement of said rear core section, cushioning means for said rear core section, said cushioning means comprising a block of foam material under compression resting on the base of said case, a plurality of cooperating electrical contacts including stationary contacts carried by said cover and movable contacts, means coupling said movable contacts to said front core section for movement thereby between one operative position in which said contacts are closed and another operative position in which said contacts are open, means biasing said front core section to a forward position in which said core sections are separated from one another and said movable contact is in one of said operative positions, and means for energizing said winding to draw said core sections together and thereby move said movable contact to the other of said positions, said foam material absorbing the energy of impact of said front core section with said rear core section.

5. A relay-contactor according to claim 4, in which said coupling means comprises a switch actuating member extending through an opening in said cover and in which an auxiliary contactor unit is removably mounted on said cover and comprises a stationary contact and a movable contact in position to be engaged and actuated by said actuating member.

6. A relay-contactor comprising a case, a plurality of stationary contacts mounted on said case, means defining cells encompassing said stationary contacts, said cells being open at their outer ends, movable contacts cooperating with said stationary contacts, electromagnetic actuating means in said case, a switch actuating member extending through said case into said cells to connect said actuating means to said movable contacts, an auxiliary contactor unit removably mounted on said case with a portion fitting into at least one of said cells, said unit comprising a stationary contact and a movable contact in position to be engaged and actuated by said actuating member.

7. A relay-contactor according to claim 6, in which each of said cells has a base portion and a side wall portion with a slot through said side wall adjacent said base and in which a contact strip forming one of said stationary contacts is inserted through said slit and rests on said base, said strip fitting tightly in said slit and being thereby frictionally held in position.

8. A relay-contactor comprising a case having a base, side walls and a removable closure opposite said base, a plurality of stationary contacts on said closure, movable contacts associated with said stationary contacts, said movable contacts being movable between a closed position in which they engage said stationary contacts and an open position in which said contacts are disengaged 7 and means for actuatingsaid movable contacts, said actuating means comprising an electromagnet in said case, said electromagnet comprising a coil and a core of magnetically permeable material, said core being divided into two complemental sections, namely a rear section disposed between said coil and said base and a front section between said coil and said closure means connecting said front core section with said movable contacts, said core sections being normally separated and being drawn toward one another when said coil is energized to draw said front core section toward the rear core section and said base, said closure engaging said coil and pressing said coil and rear core section toward said base to compress said cushion means, said coil being thus held between said rear core section and closure and being other- 5 position comprises elastic foam material.

References Cited in the file of this patent UNITED STATES PATENTS 2,399,575 Schleicher Apr. 30, 1946 2,616,998 Sala Nov. 4, 1952 2,884,499 Weber Apr. 28, 1959 2,889,426 Heller et a1 June 2, 1959 2,908,784 Kuhn et a1 Oct. 13, 1959 2,929,899 'Filliette ,'Mar. 22, 1960 15 2,951,922

Myrent et a1. Sept. 6, 1960

Images