CA1048577A - Electromagnetic reed switch - Google Patents

Abstract

BERNARD EDWARD SHLESINGER, JR.
AND CHARLIE D. MARINER

ELECTROMAGNETIC REED SWITCH

ABSTRACT
A reed switch comprising a base plate, an electromagnet and a magnetic reed having portions supported by the base plate and in close proximity to each other, the electromag-net including a core and a coil, conductor means supported by the base plate and including a contact portion, the mag-netic reed including a free end having a thin hinge facing the core, and the magnetic reed including a contact portion, the conductor means contact portion and the magnetic reed contact portion being positioned for contact engagement and disengagement with each other, whereby upon activation of the electromagnet, the magnetic reed contact portion will be drawn to or away from the conductor means contact portion by virtue of the hinge to open or close a circuit.

Description

1~)485~7 This invention relates in generaI to reed switch devices.
HISTORICAL BACKGROUND
In the past, electromagnetic reed switches have been ` quite complex and bulky. For the most part, the electroreed devices include a coîl but do not have a core, and the coil is disassociated with the support envelope of the reeds, Typical devices of this type are illustrated in Peek, Jr, United States Patent No. 2,898,422; Gomperts et al United States Patent i~o. 3,218,406; Juptner United States Patent No.

2,957,961; Kalb, United States Patent No 2,303,474, and Brown et al United States Yatent No. 2,653,199 among others.
Further, most reed switches which are not operated by a permanent magnet but use a field coil are mounted with the reeds extending from opposite ends of the envelope. Except-ions to this are shown in Van Wagnerer et al United StatesPatent No. 3,247,343; Gomperts et al United States Patent No

3,218,406 and DeFalco United States Patent No, 3,283,274 In general these patents disclose parallel reeds extending from the same end of the envelope and mounted adjacent one another in a single base. In the past, it has been the custom to form both reeds from magnetic material. Further, it has been known in the past to produce additional flexibility to the reed by forming a portion of lesser thickness than the main reed por-tion as disclosed in DeFalco and Gomperts referred to above as ; 25 well as Scheepstra et al United States Patent No. 3,258,557.
It has, however, not been the custom to mount an electromagnet which includes the coil and the core so as to extend in the same general direction and in adjacent relationship with a ~; reed such as a non-magnetic reed and a magnetic reed.
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~485~7 Thus, for the most part, it should be noted ~hat the application of a coil is common but the use of a coil and a core in conjunction with the reeds themselves is uncommon.
The purpose of having two reeds of magnetic material is ob-- 5 vious in that they themselves act as the core for transferring flux from one through the other and thus drawing them togeth-er in contact engagement. The use of a core in conjunction with a coil and a reed is broadly implied in Brown et al United States Patent No. 2,653,199 and Kalb United States Pa-tent No, 2,303,474. The devices illustrated by these latter two patents, however, do not in any way permit any sufficient reduction in size from what is presently known in the art to-day nor do they teach the relationship of core, coil and reed of this invention, In addition to the above, electromagnets, when used in switching, generally have been quite complex with little a-bility to focus the magnetic field. For the most part, the coils have been used only to produce a large flux field with-in the area encompassed by the coil. Very little attempt , 20 has been made to concentrate the flux field at a specific point. Brown et al United States Patent No. 2,653,199 makes some attempt to do this. Magnetic coils used in reed switch-ing have generally, with the possible exception of Brown, not attempted to utilize a core member which will concentrate the 25 flux field. Rypinsky United States Patent No, 1,972,319 shows the idea of wrapping a coil of wire about a central core mem-ber each being insulated one from the other, It could be said that the coil in Rypinsky would act about the inner core mem-ber although in this instance there is no attempt to utilize 30 the principle for directing a flux field to a point in the manner of this invention, , --3--~Q48~7~' OBJECTS AND SUMMARY
It is therefore an object of this invention to provide an electromagnetic reed switch which allows for greater re-duction in size and an increase in low carrying capacities substantially greater than heretofor.
It is a further object of this invention to provide an electromagnetic reed switch which can be inexpensively and readily manufactured.
Another object o this invention is to provide an elec-tromagnetic reed switch which has great durability and cantake severe strain and stress.
Yet a further object of this invention is to provide an electromagnetic reed switch which incorporates therein a magnetic conductive reed and a non-magnetic conductive reed thereby providing for rapid make and break unachieveable with prior reed switches in which the reeds are both of mag-netic conductive material.
Still a further object of this invention is to provide an electromagnetic reed switch which is substantially planar utilizing primarily two dimensions.
A still further object of this invention is to provide an electr~magnetic reed switch having many options of opera-tion including various on-off combinations.
It is a further object of this invention to provide an electomagnetic reed switch which has an extremely rapid clo-sing time.
Yet another object of this invention is to provide an electromagnetic reed switch in which the spring element of the reed has been cold-worked so as to completely change the crystalline structure of the metal in the area of the cold-work to provide a spring which is durable and extremely ~ -4-1~8S7~

f lexib le .

-4a-~48577 Yet another object of this invention is to provide an electromagnetic reed switch having contacts at the same end of the capsule thereby permitting substantial reduction in size.
Yet another object of this invention is to provide an electromagnetic reed switch which incorporates plural electro-: magnets for on and off operation.
Another object of this invention is to provide an electro-magnetic reed switch which has a strong snap action so as to crunch or otherwise break through any outside build-up increasing the longevity of the switch and eliminate malfunction due to carbon build-up.
i Yet a further object of the invention is to provide an electromagnetic reed switch whichhas good contact wipe char-acteristics.
Still a further object of this invention is to provide a reed switch which improves conductivity characteristics with use.
A further object of this invention is to provide an electromagnetic reed switch which can be adapted to many shapes and forms.
Still a further object of this invention is to provide an electromagnetic reed switch capable of being used in linear and radial configurations and combinations.
Still a further object of this invention is to provide an electromagnet for use with reed switch devices whereby the force field can be concentrated in a specific point for reed contact operation.
Another object of this invention is to provide an elec-tromagnet for reed switches having a core with a coil wrap-ped around which can be bent or formed to conical, cylindri-cal or other configurations and whereby the end of the core will act as the focusing point for the magnetic field.

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A further object of this invention is to provide an electromagnet for reed switches having a core and coil wind-ing about said core in which the electromagnet forms an Archimedes spiral or ring with at least one end of the core positioned so as to direct the magnetic field in order to switch a magnetic reed.
A still further object of this invention is to provide an electromagnet for reed switches having a coil and core in which the ends of the core are directed towards each other for the purpose of actuating reed devices.
Still another object of this invention is to provide an electromagnet having a core which is conductive and is itself a conductor and which core has one end so directed as to con-centrate a flux for pulling a magnetic reed towards the core end which core end is itself a contact surface for the mag-netic reed.
In summary therefore, this inven~ion is directed to el-ectromagnetic reed switches and electromagnets therefore in-cluding a coil, core, and a reed therefor which permit sub-stantial reduction in size over present reed switch deviceswhile maintaining substantially the same capabilities and ca-pacities and these and other objects of this invention will be apparent from the following description and claims.
The invention in its broadest aspects consists of a reed s~itch comprising a support, an electromagnet and a magnetic reed having portions supported by said support and in close proximity to each other, said electromagnet including a core and a coil, conductor means supported by said support, said .:
conductor means including a contact portion, said magnetic reed including a free end having a thin hinge facing said core, said magnetic reed including a contact portion, said ~ -6-..

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10~7 conductor means contact portion and said magnetic reed con-tact portion being positioned for contact engagement and dis-engagement with each other, whereby upon activation of said electromagnet said magnetic reed contact portion will be drawin to or away from said conductor means contact portion by virtue of said hinge to open or close a circuit.

In the accompanying drawings which illustrate by way of example various embodiments of this invention:
Fig. 1 is a side elevational view shown in cross section of the invention;
Fig. lA is an enlarged fragmentary cross sectional view of the embodiment shown in Figure 1 taken along the lines la-la and viewed in the direction of the arrows;

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Fig, 2 is a cross sectional view of the embodiment shown in Figure l taken along the lines 2-2 and viewed in the direction of the arrows Fig, 3 is a side elevational view in cross section showing another embodiment of the invention;
Fig, 4 is a sectional view of the embodiment shown in Figure 3 taken along the lines 4-4 and viewed in the direc-tion of the arrows;
Fig. 5 is a side elevational view in cross section of another embodiment of the invention;
Fig. 6 is a sectional view of the embodiment shown in Figure 5 taken along the lines 6-6 and viewed in the direc-tion of the arrows;
Figs, 7, 8, 9 and 10 are sectional views of additional ~, embodiments of this invention;
Fig, 11 is another embodiment of this invention in cross section;
Fig. 12 is a sectional view of the em~odiment shown in Figure 11 taken along the lines 12-12 and viewed in the di-2Q rection of the arrows;
Fig. 13 is an elevational view shown in cross section of yet a further embodiment of the invention;
Fig, 14 is a sectional view of the embodiment shown in Figure 13 taken along the lines 14-14 and viewed in the direction of the arrows;
Fig, 15 is an elevational view in cross section showing yet a further embodiment of the invention;
Fig, 16 is a sectional view of the embodiment shown in Figure 15 taken along the line 16-16 and viewed in the di-, 30 rection of the arrows;

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lQ~18S77 Figs, 17, 18 and 19 are elevational views in cross sec~tion showing still further embodiments of the invention;
Fig. 20 is a sectiunal view of the embodiment shown in Figu~e 19 taken along the lines 20-20 and viewed in the direction of the arrows;
Fig. 21 is a fragmentary top plan view of still a fur-ther embodiment of this invention;
Fig, 22 is a sectional view of the embodiment shown in Figure 21 taken along the lines 22-22 and viewed in the di-rection of the arrows.
Fig. 23 is a cross sectional top plan view of a furtherembodiment of this invention. The cross section is taken below the top surface of the cover.
Figs. 24 and 25 are cross sectional views of the embod-iment shown in Figure 23 taken along the lines 24~24 and 25-25 respectively and viewed in the direction of the arrows.
In these figures, the top surface of the cover is shown.
FIGURES l THROUGH 18 In FIG~RE 1, the switch capsule is generally designated by S. The capsule S comprises a base 2 and a cover 4. The base 2 and cover 4 may be ceramic, plastic, or glass or the like. In the base 2 is a conductive magnetic reed 6 and a conductive non-magnetic reed 8 in side-by-side generally parallel relationship. Adjacent the non-magnetic reed is mounted an electromagnet 10 comprising a core 12 having wrapped thereon a coil 14 terminating in pins 15 of the leads 16. The coil 14 is a wrapping of typical electro-magnetic insulated wire with the desired number of turns wrapped around the core 12 in order to produce a sufficient magnetic field at the end 18 of the core 12. The core it-~ -8-1~48577 self is of any typical electromagnetic core material such as iron, nickel or the like alloys. The core material may have substantial conductivity characteristics or be coated with a conductive material for purposes here and after described.
The ~agnetic reed 6 includes a foil thin hinge 20 of less than ,003 inch thickness.
It will be noted that the reeds 6 and 8 extend through the base 2 for purposes of electrical connection.

-8a-1~48S7~7 It will now be obvious that upon energization of the coil 14, the core 12 will be magnetized and the force field will be concentrated about the end 18 so as to draw the mag-netic reed 6 towards the non-magnetic reed 8 thereby to close a circuît.
In FIGURE 3, it will be noted that a pair of reeds 6 are used in conjunction with a pair of reeds 8 on either side of the electromagnet 10. On the left, the non-magnetic reed 8 is positioned between the electromagnet 10 and the magnetic reed 6 whereas on the right, the magnetic reed is positioned between the electromagnet 10 and the non-magnetic reed 8. The non-magnetic reed 8 has a bent end 22.
Upon activation of the electromagnet 10, the magnetic reeds 6 will be drawn towards the electromagnet 10 to close a circuit on the left and to open a circuit on the right.
The core 12 may have its end 24 flattened or otherwise shapedto form a T to provide a better force field, In FIGURE 5, the base 2 includes two electromagnets 10, A magnetic reed 6 is positioned between two non-magnetic reeds 8 with the electromagnets 10 facing each other and out-side of the non-magnetic reeds 8. In operation, the magnetic reed 6 is drawn either to the left or to the right of the non-magnetic reed depending upon which of the two electromagnets 10 are activated.
In the arrangement shown in FIGURE 7, a conductive non-magnetic reed 30 is shown to be wider than magnetic reeds 6 and an engagement therewith, The dotted line position indi-cates the position of the magnetic reeds 6 when the electro-magnet 10 is turned on. FIGURE 8 shows a reversal of the position of the magnetic reeds 6 and the non-magnetic reed 30. In FIGURE 7, the circuits are broken whereas in FIGURE

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8, the circuits are made. It is obvious that the magnetic reed 6 may be a wide reed 30 operating against or away from two or more non-magnetic reeds 8.

-9a-- ~048S77 In FIGURES 9 and 10, the reeds 6 make contact as in FIGURE 9 or break contact as in FIGURE 10 with a sleeve 32.
The sleeve 32 is conductive and connected to an electrical lead 33 extending through base 2. Instead of a sleeve 32, a cage,

5 or ring supported by posts might be used.
In FIGURES 11 through 17, the electromagnets 34 instead of being post-like as in FIGURES 1 through 10, are coiled or helically shaped. FIGURES 11 and 12 show the electromagnet 34 as being concially shaped. The core of the electromagnet 10 34 provided with a conductive terminal end 36 and the core itself is conductive. Note also that the electromagnets in FIGURES 15 and 16 also have terminal ends 36 which project for connection to electrical leads, the electromagnets 34 having conductive cores. In FIGURES 11 and 12 and 15 and 16, the 15 magnetic reeds 6 close against the contact ends 37 of the conductive cores of the electromagnets 34 to made a circuit.
In FIGURES 13, 14 and 17, the magnetic reed 6 engages a non-magnetic reed or magnetic reeds 8 as the case may be to close a circuit. The coiling of the electromagnet 34 permits a 20 much smaller package. Though the overall len~th of the core is the same, the height can be reduced from a post-like con-figuration as shown in FIGURES 1 through 10. In FIGURES 15, 16 and 17 electromagnets 34 are intertwined.
The operation of the devices shown in FIGURES 11 through 17 is similar to that described in FIGURES 1 through 10.

In FIGURE 18, a magnetic reed 38 is L-shaped and extends above an L-shaped non-magnetic reed 40. The action is in a downward direction upon activation of the electromagnet 10.
26 In FIGURE 19, instead of there being a non-magnetic reed, there is a contact button 42 for the L-shaped magnetic reed 44.
It will be noted that rather than having a post electro-magnet 10, - lOa-.

1~48S77 the electromagnet is a flat Archimedes coil 46 as best shown in FIGURE 20, The contact button 42 is secured to a con-ductor 48 extending through the base 2. The configuration shown in FIGURES 19 and 20 allows for a very low profile switch package, In FIGURE 21 and 22, the electromagnet 50 has the core end 52 projecting upwardly within a conductive non-magnetic ring 54. Above the conductive magnetic ring are mounted a series of magnetic reed fingers 56. The reed fingers are terminated in printed circuitry 58. The non-magnetic ring conductor 54 is also terminated in printed circuitry 60 and other printed circuits may be provided for the electromagnet 50 in place of the standard pin conductors 15.

In FIGURES 23 through 25, a series of magnetic reeds 62 are provided in an in-line arrangement. The magnetic reeds close on a series of conductors 64 also in an in-line arrange-ment.
Mounted in the support base or plate 66 is an electromag-net 68 of a generaIly C-configuration with the ends 70 posi-tioned directly beneath the magnetic reeds 62. It will be obvious that upon activation of the electromagnet 68, the mag-netic reed 62 will be drawn downward towards the ends 70 to close upon the conductors 64.
While this invention has been described as having a pre-ferred design, it will be understood that it is capable of further modification. This application is, therefore, intend-ed to cover any variations, uses or adaptations of the inven-tion following the general principles thereof and including such departures from the present disclosure as come within known or customary practice in the art to which this inven-,~ -11-.
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3L~)48577 tion pertains and as may be applied to the Pssential features hereinbefore set forth and fall within the scope of this in-vention or the limits of the appended claims.

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Claims (58)

Having thus described our invention what we claim is:

1. A reed switch comprising:
a) a support, b) an electromagnet and a magnetic reed having portions supported by said support and in close proximity to each other, c) said electromagnet including a core and a coil, d) conductor means supported by said support, e) said conductor means including a contact portion, f) said magnetic reed including a free end having a thin hinge facing said core, g) said magnetic reed including a contact portion, h) said conductor means contact portion and said magnetic reed contact portion being positioned for contact engagement and disengagement with each other, i) whereby upon activation of said electromagnet said magnetic reed contact portion will be drawn to or away from said conductor means contact portion by virtue of said hinge to open or close a circuit.

2. A reed switch as in Claim 1 and wherein:
a) said conductor means includes said core.

3. A reed switch as in Claim 2 and wherein:
a) said conductor means contact portion includes said core.

4. A reed switch as in Claim 1 and including:
a) an envelope supported by said support and enclo-sing said electromagnet and said magnetic reed.

5. A reed switch as in Claim 1 and wherein:
a) said core is a helix and said coil is wrapped about said helix.

6. A reed switch as in Claim 5 and wherein:
a) said helix lies in a single plane.

7. A reed switch as in Claim 5 and wherein:
a) said helix extends through more than a single plane.

8. A reed switch as in Claim 5 and wherein:
a) said helix is generally conical.

9. A reed switch as in Claim 5 and wherein:
a) said helix is generally cylindrical.

10. A reed switch as in Claim 6 and wherein:
a) said magnetic reed has its free end extending over said helix and said magnetic reed contact portion moves in a direction substantially vertical to said support.

11. A reed switch as in Claim 1 and wherein:
a) said magnetic reed's free end moves in a direc-tion substantially horizontal to said support.

12. A reed switch as in Claim 1 and wherein:
a) said conductor means terminal portion is mounted in said support.

13. A reed switch as in Claim 12 and wherein:
a) said conductor means is mounted adjacent said core.

14. A reed switch as in Claim 13 and wherein:
a) said conductor means in positioned between said magnetic reed and said core.

15. A reed switch as in Claim 12 and wherein:
a) said conductor means is mounted adjacent said magnetic reed.

16. A reed switch as in Claim 15 and wherein:
a) said magnetic reed is positioned between said conductor means and said core.

17. A reed switch as in Claim 1 and wherein:
a) said core, said magnetic reed, and said conduc-tor means are supported in said support in substantially par-allel relationship.

18. A reed switch as in Claim 1 and wherein:
a) said core includes a tip portion bent in the direction of said magnetic reed.

19. A reed switch as in Claim 1 and wherein:
a) said conductor means includes a non-magnetic reed.

20. A reed switch as in Claim 19 and wherein:
a) said non-magnetic reed has a free end and said free end is in length approximately the length of said magnet-ic reed and is substantially parallel thereto.

21. A reed switch as in Claim 20 and wherein:
a) said core has a free end and said free end is in length approximately the length of one of said reeds and is substantially parallel thereto.

22. A reed switch as in Claim 1 and including:
a) a plurality of said magnetic reeds spaced from said core.

23. A reed switch as in Claim 22 and including:
a) said conductor means including a plurality of conductors spaced from said core.

24. A reed switch as in Claim 23 and wherein:
a) at least one of said conductors is positioned between said core and said magnetic reeds.

25. A reed switch as in Claim 23 and wherein:
a) at least one of said magnetic reeds is position-ed between said core and one of said conductors.

26. A reed switch as in Claim 19 and including:
a) a plurality of said non-magnetic reeds spaced from said core.

27. A reed switch as in Claim 26 and wherein:
a) said non-magnetic reeds are positioned between said magnetic reed and said core.

28. A reed switch as in Claim 26 and wherein:
a) said magnetic reed is positioned between said non-magnetic reeds and said core.

29. A reed switch as in Claim 19 and including:
a) a plurality of magnetic reeds spaced from said core and between said core and said non-magnetic reed.

30. A reed switch as in Claim 19 and including:
a) a plurality of magnetic reeds spaced from said core and said non-magnetic reed being disposed radially be-tween said core and magnetic reeds.

31. A reed switch as in Claim 1 and including:
a) a plurality of said electromagnets supported by said support each having a coil and a core.
b) said electromagnets being positioned on oppo-site sides of said magnetic reed.

32. A reed switch as in Claim 31 and wherein:
a) said conductor means includes a plurality of non-magnetic reeds, and b) at least one non-magnetic reed being positioned on opposite sides of said magnetic reed and each associated with one of said electromagnets.

33. A reed switch as in Claim 19 and including:
a) a plurality of non-magnetic reeds, and b) at least two of said electromagnets surrounding said reeds.

34. A reed switch as in Claim 20 and wherein:
a) said magnetic and non-magnetic reeds have their free ends extending over said core and said magnetic reed free end moves in a vertical direction relative to said support.

35. A reed switch as in Claim 34 and including:
a) a plurality of said magnetic reeds mounted above said non-magnetic reed.

36. A reed switch as in Claim 34 and including:
a) a plurality of non-magnetic reeds mounted above at least one magnetic reed.

37. A reed switch as in Claim 34 and including:
a) a plurality of non-magnetic and magnetic reeds operating in pairs.

38. A reed switch as in Claim 37 and wherein:
a) said operating pairs of magnetic and non-magnet-ic reeds are displaced from said core.

39. A reed switch as in Claim 37 and wherein:
a) said operating pairs of magnetic and non-magnet-ic reeds are arranged in a row.

40. A reed switch as in Claim 34 and wherein:
a) said core is a helix lying in a single plane and mounted in the horizontal plane of said base.

41. A reed switch as in Claim 1 and wherein:
a) said hinge is foil thin.

42. A reed switch as in Claim 1 and wherein:
a) said hinge is less than .003 inches in thickness.

43. A reed switch as in Claim 1 and including:
a) a plurality of said magnetic reeds engaging said contact means portion, and b) at least two of said electromagnets surrounding said reeds.

44. A reed switch as in Claim 29 and including:
a) a plurality of said electromagnets, and b) said electromagnet cores being intertwined.

45. A reed switch comprising:
a) a support b) an electromagnet and a magnetic reed having portions supported by said support and in close proximity to each other.
c) said electromagnet including a core and a coil, d) said coil being wrapped about the surface of said core and conforming with the surface of said core in contact therewith, e) conductor means supported by said support, f) said conductor means including a contact portion, g) said magnetic reed having hinge of less than .003 inch thickness and including a contact portion positioned for contact engagement and disengagement with said conductor means contact portion.
h) whereby upon activation of said electromagnet said magnetic reed contact portion will be drawn to or away from said conductor means contact portion to open or close a circuit.

46. A reed switch as in Claim 45 and wherein:
a) said core is a post.

47. A reed switch as in Claim 45 and wherein:
a) said core forms a conical helix.

48. A reed switch as in Claim 45 and wherein:
a) said core forms a cylindrical helix.

49. A reed switch as in Claim 45 and wherein:
a) said core is a spiral lying substantially in a single plane.

50. A reed switch as in Claim 45 and wherein:
a) said core has at least one end unwrapped.

51. A reed switch as in Claim 50 and wherein:
a) said one unwrapped end includes a bent portion directed toward said magnetic reed.

52. A reed switch comprising:
a) a support, b) an electromagnet and a magnetic reed having por-tions supported by said support and in close proximity to each other, c) said electromagnet including a core and a coil, d) said coil being wrapped about the surface of said core and conforming with the surface of said core and in contact therewith, e) conductor means supported by said support, f) said conductor means including a contact portion, g) said magnetic reed including a contact portion positioned for contact engagement and disengagement with said conductor means contact portion, h) said electromagnet being coil shaped, i) whereby upon activation of said electromagnet, said magnetic reed contact portion will be drawn away from or towards said conductor means contact portion to open or close a circuit.

53. A reed switch as in Claim 52 and wherein:
a) said conductor means contact portion includes said core.

54. A reed switch as in Claim 52 and wherein:
a) said conductor means includes said core, and b) said electromagnet substantially encoils about said magnetic reed.

55. A reed switch as in Claim 52 and wherein:
a) said electromagnet substantially encoils about said magnetic reed.

56. A reed switch as in Claim 52 and wherein:
a) said electromagnet substantially encoils about said conductor means.

57. A reed switch as in Claim 52 and wherein:
a) said electromagnet substantially encoils about said magnetic reed and said conductor means.

58. A reed switch as in Claim 56 and wherein:
a) said magnetic reed is positioned outside of said electromagnet.