US2491907A - Polarized magnetic switch structure - Google Patents

Description

Dec. 20, 1949 l H. REiFEL EZTAL l 2,4919907 POLAR-IZBB MAGNETIC SWITCH STRJYIv Filed June l1, i946 j my 5. f

Patented Dec. 20, 1949 2,491,907 PoLAlt-IZED MAGNETIC" sWrrcH STRUCTURE Harry ei'felQfWaltham, andIer-bert Weight'- man, Scituate, Mass., assignors, by mesne as# signmert's, to Stevens-ArnolrL Inc.,` Boston;`

ass., acdrpora'tion of Massachusettsl Application .rune 1.1, 194.6, serial- Nt.` siasi-'i 4* claims. (ol. too-:93)

This invention relates tolmagntic'swtches, and has as an object, theY p r'ovision'of.A a' simple, inexpensive, magnetic switch capable' of high speed operation.

The high speed, magnetic' switches proposed heretofore, have included pairs of metall. reed armatures supported as cantilever beams in the opposite endsof sealed tubes, with theii` free ends overlapping. When a coil woundaround such' aY pair ofy armatures is energized, their' free ends are attracted together through beingv magnetized, and close an electric circuit in which they are included. Such switches-areexpensive to manufacture, their speed? ofiv operation is too low for many duties', and they have' the disadvantage that the free endsofA their armatures bounce away from each other when they strike, causing erratic operation.

This invention provides a highV speed', magnetic switch havingV but a single reed:v armature supported as a cantilever beam, the free end of which extends between oppositely" supported membersv of magnetic metal; whereby uponjthe energize'- tion of an encirclin'gcoil, thearmature isattracted by one* member' an'd' repelledi by the other member, .resulting in a v'eryT high' operating speed. Through" the free end' of the armature" contacting one magneticmember when the energizing coilis'v energized; and contacting the other' magnetic member' when` the coil is deenergized, a

double pole switch`- is' provided. Dampin'gis applied to' the' armature"between'l its ends:k for" preventing bouncing; The construction is inexpensive since it comprises a simple channel member having turned over ears which press upon spacers of insulating material which hold the armature and the damping and magnetic members in position.

The invention will now be described with reference to the drawing, of which:

Fig. 1 is a side elevation, partially in section, of an assembled relay embodying this invention;

Fig. 2 is a plan view looking downwardly upon the channel of Fig. 1 with the armature and the damping and magnetic members assembled therein, and

Fig. 3 is a sectional view along the lines 3-3 of Fig. 2.

Referring rst to Figs. 2 and 3, the channel member IU which may be of brass, has the spaced, 'n

parallel sides II, and has open ends. The brass strip I2 extends through the channel in contact with the bottom thereof, and has one end extending beyond the right hand end, facing the drawing, of the channel for providing an e1ectrica'i wiring' cone' rlfhe stri'p I3 of mag# netic metal is's'ta d n top of the stripf I2 at the left handend d f the channel Il] `rand cXtendS inwardly into the channel' as illustrated by Fig; 3. The spacer strip- I4. electric insulating material is stacked on the strip` I'3. The outer fen'd of the armature i5 of lmagretic metal, stacked o'n ,theI strip le, andA the sti-ip' Isjqf brass is stacked on' the outer end ofthe ariina'ture. he outer end of the r'netalv damping mm Ill; is stacked on thev strip at, andtneprassf pila iss'tacked on the member il' andhas its ou,te'1j endy extending be'- yond thev left hand end' o'f the! channelior prov iding an electricalwi g connection'. The strip I@ of electric insult g at'ejr'ia'l' is" stacked on the strip I8, andthe arts" 2B' which are extensions' of the sides I I; of, tj,`hey channel; I, areibent over as illustrated' by Figsz and 3, and press' `against the strip I9 and hold the described stacked' assembly in' position;

The free inner' end' f the ar matureY f5 and; the inner end of the strip I3 extend substantially the same distance'into thev channel I D.; The strip 2! of magnetic meta supportedin the right hand end of thegchan between the'space'rs 22 and 23 of Xelectriciri`s}`1 l'ai'. ing'j' materiau,l theear extensions 24 of the sides IIfof the channel'being bent over so as to'pre's's"` against thespacer 22 for holding the member* 2|; in position.

The inner end of the member 2| overlaps the inner end of the armature I'Sas illustrated by Fig. 3. Theo'utr end`25 of the member 2'I eX- t'ehds perpendicular" t'ofthe member 2|` for eg;- tending'V the direct' magnetic path' as' will loe-de# scribed.

Both sides of the inner end of the armature have suitable electric contact surfaces provided thereon as do the lower surface of the inner end of the member 2| and the upper surface of the inner end of the strip I3.

The armature I5 is bent between its ends so as to have a humped portion 26 which is contacted by the downwardly extending inner end of the damping member II. Thescrew 28 is threaded into the inner end of the strip I8, and its inner end contacts the member I'I and presses its inner end against the armature I5 Referring now to Fig. 1, the assembled relay illustrated, includes the enclosing tube 3i) having the base 3l with thesocket prongs 32, 33, 34, 35 and 3%. Themagnetizing coil 31 encircles the channel and supports same within the tube 3U, thespacer 38 supporting the coil between the walls of the tube.lThe wires 39 and 40 connect lthe ends of the coil to thesocket prongs 33 and 35 respectively. The wire 4I connects the strip I2 to theprong 36. Thewire 42 connects themember 25 to theprong 32, and thewire 43 connects the strip I8 to theprong 34.

In operation, when the coil is deenergized, the inner end of the armature touches the inner end of the strip I3 thereby closing a circuit in which the `prongs 34 and 36 are connected. When the coil is energized as by the application of direct current to theprongs 33 and 35, the magnetic eld within the coil magnetizes the armature I5 and the strip I3 so that their inner ends have the same polarity, and the free end of the armature is repelled by the inner end of the strip I3. At the same time the member 2| is magnetized so that its inner end has the opposite polarity causing to attract the free end of the armature. This attraction and repulsion causes `the armature to hinge about the humped portion 26 thereof which the inner end of the damping member I1 contacts. and to move upwardly against the inner end oi the member 2l so as to close an electric circuit in which theprongs 32 and 34 are included, and to open the circuit in which theprongs 34 and 36 are connected. When the coil is again deenergized, the armature, the strip I3 and the member 2I become demagnetized, and the spring tension in the armature causes it to return its free end in contact with the inner end of the strip I3.

The damping member I1 by pressing against the armature I5 damps same against vibration and bouncing. The correct damping pressure is regulated by the adjustment of thescrew 28 which then is sealed in position as by the application of a suitable cement thereto.

Theperpendicular extension 25 of the magnetic member 2I serves to prolong the direct magnetic path between the member 2l and the left hand end of the armature when thecoil 31 is energized, thus increasing the magnetic flux and the efiiciency.

While one embodiment of the invention has been described for the purpose of illustration, it should be understood that the invention is not limited to the exact apparatus and arrangement of apparatus illustrated, as modifications thereof may be suggested by those skilled in the art without departure from the essence of the invention.

What is claimed is:

1. A magnetic switch comprising a support, a flexible reed, contact making, armature of magnetic metal supported as a cantilever beam from one end of said support, a rst member of magnetic metal extending alongside said armature and insulated therefrom, a contact member of magnetic metal insulated from said armature and supported from the other end of said support and having one end overlapping the free end of said armature, a damping reed of spring metal supported as a cantilever beam from said support, and having its xed end spaced from the xed end of said armature, and having its free end in contact with said armature between its ends, and pressing the free end of said armature against said rst member, and a coil around said armature and members for causing, when energized, said free end of said armature to be repelled by said first member and to be attracted by said second member.

2. A magnetic switch as claimed in claim l, in which the armature is bent towards and away from its point of contact with the damping reed.

3. A magnetic switch as claimed in claim 1, including adjustable means, said adjustable means being attached to the support and contacting the damping reed between its ends, and forcing its free end against the armature.

4. A magnetic switch as claimed in claim 1, in which the armature is bent towards and away from its point of contact with the damping reed, and including adjustable means, said adjustable means being attached to the support and contacting the damping reed between its ends, and forcing its free end against the armature.

HARRY REIFEL. HERBERT G. WEIGHTMAN.

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

UNITED STATES PATENTS Number Name Date 1,693,491 Ogden Nov. 27, 1928 2,029,266 Lecce et al. Jan. 28, 1936 2,053,102 Palmer Sept. 1, 1936 2,245,391 Dickten, Jr June 10, 1941 2,257,900 Crum Oct. 7, 1941 2,264,022 Ellwood Nov. 25, 1941 2,264,746 Ellwood Dec. 2, 194.1 2,275,531 Lakatos Mar. 10, 1942 2,277,443 Livingston Mar. 24, 1942 2,334,897 Baker Nov. 23, 1943 2,397,123 Brown Mar. 26, 1946

Images