Патент USA US3048759код для вставки
Aug- 7, 1952 G. N. KOEHLER 3,048,749 ELECTRIC RELAY Filed March 2, 1959 2 Sheets-Sheet l Aug- 7, 1962 G. N. KOEHLER 3,048,749 ELECTRIC RELAY Filed March 2, 1959 2 Sheets-Sheet 2 , g. Q,‘ I, trite , States atom 3,048,749 1 Patented Aug. 7, 1962. 2 1 strength of the current supplied does not exceed a certain limit. 3,048,749 ELECTRIC RELAY Gérard Noel Koehler, Saint-Cloud, France, assignor to Compagnie des Machines Bull (Societe Anonyme), Paris, France Filed Mar. 2, 1959, Ser. No. 7%,693 Claims priority, application France Mar. 6, 1958 5 Claims. (*Cl. 317-165) The invention therefore concerns an electromagnetic relay comprising normal and off-normal contacts, a ?xed magnetic yoke constituting with the magnetic core of the electromagnet and a rigid armature resting on the said yoke the magnetic circuit, in which the armature is main tained against a bearing surface of the yoke by an initially plane leaf spring and ?xed on one side to the said arma-= The present invention concerns improvements in the 10 ture and on the other side to a supporting member fast with the yoke in such manner that the said spring leaf construction of low-power relays. receives a certain ?exure well below vits elastic limit Relays comprise, basically, an electric circuit which includes a coil, a magneticvcircuit comprising a core, an armature and a spring device which returns the armature when the armature is in contact with its normal contact or contacts. For a better understanding of the invention and to to the inoperative position, as also a system of contacts, 15 show how it may be carried into effect, the same will some of which are closed when the coil is energized (off now be described, by way of example, with reference normal contacts), while the others are closed when the to the accompanying drawings, in which: coil is not energized (normal contacts). All these ele FIGURE 1 is an elevational view of a relay according ments should be so arranged as to ensure great safety even ‘after prolonged operation, while being of simple 20 to the invention, FIGURE 2 is a plan view of the relay, construction. A large number of known constructions ‘FIGURE 3 is an elevational view of a part of the relay, do not meet these requirements. It has been proposed FIGURE 4 is a plan view corresponding to FIGURE 3, in particular to employ coil springs as the return spring FIGURES 5 and 6 are fragmentary perspective views for the armature. This type of spring tends to oscillate for some time after the triggering of its action and can 25 illustrating two modi?cations of the relay, and FIGURE 7 is a perspective view of the relay. consequently produce variations in the time of operation In FIGURES l and 2 the illustrated relay comprises and faulty contact-making. Flat springs supporting the armature have also been proposed, but in this case the armature was separated by an air gap from the ?xed member supporting the said spring, which increased the reluctance of the magnetic circuit. Pre-bent leaf springs (bending by exceeding the elastic limit) have also been proposed. This arrangement does not afford the same length of service as a plane spring leaf operating below its elastic limit. In addition, the adjustment of the pres 35 sure of the armature on its contacts has sometimes been effected by modifying the bend of such a spring, which could not give constant results. In some constructions, the magnetic circuit comprises defective joints between the armature and one or more ?xed members of the said circuit when the armature is in the inoperative position, whereby the reluctance of the circuit is increased. With the use of a pin joint or knife-edge joint, it is necessary an external casing l, a movable armature 3, a return spring 2, an energizing coil 4 wound around a magnetic core 12, the latter being ?xed to a member '7 which forms a yoke for the magnetic circuit and which is being ex tended towards the left and secured to a pin shown at 13 in FIGURE 1 and at 24? in FIGURE 2. The lead-in wires of the electric circuit are shown at 9, the lead-out pins being the pins l8, 1% and it}, 2.1 (one pin being designated by like references in FIGURES i and 2). The relay comprises two ?xed double contacts 3a and 8b connected to the pins 17, 21 and 17, 19 respectively, the ?rst through the member 16, and the second through the member 14, which comprises a portion 14a. The lower cheek of the frame 6 of insulating material of the coil is extended to a point below the end of the member 4 anchored in the said frame so as to support the latter with respect to the yoke 7, which serves as a level refer pendicular to the movement in order to avoid jamming. 45 ence. The spring 2 is ?xed at the points 11 and 18, on the one hand to the armature 3 and on the other hand to This results in an ill-de?ned initial position of the arma a member 5 screwed on the yoke 7 of the magnetic ture, which causes dispersion in the operating times and circuit. increases the danger of jamming of the armature at the Referring now to FIGURES 3 and 4, which show the levels of the contacts as a result of transfer of metal due 50 assembly consisting of the armature 3, the spring 2 and to the electric arcs. the member 5 before its introduction into the relay, it Finally, the armature is sometimes connected to a will be seen that the spring 2 is an initially undeformed lead-out pin by a braid soldered over the said armature. ?at spring formed with a rectangular recess for receiving This arrangement is not very practical. the wider end of the armature, which recess may be An object of the present invention is to devise a relay of improved construction with a view to obviating the 55 formed simply by cutting in a thin sheet of appropriate metal. The armature has two bent-over ends forming foregoing disadvantages. a fork, which are intended to come into contact with the Accordingly, the return spring of the armature is a ?at double contacts 8a and 8b. The armature is cut from an leaf-spring, the attachment of which involves ?exure iron strip plated with silver or other appropriate metal well below its elastic limit. It is secured to the arma ture, on the one hand, and to a ?xed member fast with 60 in such manner as to provide a silver-plated zone op posite each contact. The surface of the armature is pro a ?xed yoke of the magnetic circuit on the other hand. tected by burnishing so as to leave the silver surfaces The pressure of the armature on its normal contacts is intact. When the member 5 is screwed on to the yoke adjusted by bending the said ?xed member to a variable 7, the spring is ?exed, whereby the armature 3 is applied extent. The armature is maintained in contact with the said ?xed yoke of the magnetic circuit by the said flat 65 to the contacts 8a. The pressure of the armature 3 on to allow the armature some freedom in the direction per leaf spring, whereby the reluctance of the corresponding‘ the contacts 8a can be adjusted by deforming the portion 5a of the member 5 by means of pliers. Since the mem joint is reduced. The electric circuit extends through the ber 5 is thick, this deformation is completely stable. armature, the ?at spring, the ?xed member to which the When the relay is energized, the armature. 3 is attracted spring is secured and the yoke of the magnetic circuit, so 70 by the core 12 in such manner as to reduce the reluctance that a direct soldered connection between the armature of the magnetic circuit, and the armature 3 comes into and the lead-out pin is unnecessary, at least as long as the contact with the contacts 81;. As soon as the energization 3,048,749 xi. part and presenting a surface oblique with respect to said armature, and a single leaf-spring which is initially plane, for mechanically linking said armature and said surface, a of the electric circuit is interrupted, the spring 2 returns the armature 3 to its inoperative position. When the relay is to be used for closing a circuit when energized, the ends of the said circuit must be connected to the pins 18, 2t? and 17, 19. If the relay is to open a circuit, the ends of the said circuit must be connected to the pins 13, 2t} and 17, 21. The utilization current is set up through the pins 17, i‘) or 17, 21, as required, the con tact 8a or Sb, the armature 3, the spring 2, the member 5 and the member 7, and the pin 18, 2G. In this con 10 struction, it is therefore unnecessary to provide a con nection extending from the armature 3 to a lead-out pin, said armature and spring having reciprocal forms such that the spring is curved without permanent deformation after an extremity thereof is secured to said bracket, in such a manner that the curved pro?le of said spring sub stantially lies in the prolongation of said fulcrum line. 2. An electro-mechanical relay as claimed in claim 1, wherein said leaf-spring is made sufficiently conducting so as to assure electrical linkage between said armature and said yoke. 3. An electro-mechanical relay as claimed in claim 2, the utilization circuit here extending through the spring and a part of the magnetic circuit. In addition, the joint wherein said bracket has an angle extension constituting 15 between the armature 3 and the yoke 7 is with cer 15 said oblique surface and permitting adjustment of the tainty established by the pressure exerted by the spring spring curvature. 2 both in the inoperative position and in the operative 4. In an electro-mechanical relay having an energiza position of the armature. This assists in reducing the tion coil, a magnetic yoke and an armature, an extremity parasitic reluctance of the magnetic circuit. Finally, re of which lies by a fulcrum line on a part of said yoke ferring again to FIGURE 1, it will be seen that the ?exed substantially parallel to the axis of said coil, in combina surface of the spring 2 extends in immediate proximity tion, a metallic bracket ?xed on said part and having to the pivoting edge of the armature 3: on the yoke 7. Therefore, when the armature 3 is attracted by the core a member oblique with respect to said armature, and a single leaf-spring initially uncurved ‘for electrically link ing said armature and said yoke, said spring being adapted 12-, there is no horizontal sliding of the said armature 3 on the yoke 7, and consequently no tendency for the 25 to be non-permanently curved when an extremity thereof contact 1.5 to become worn, While at the same time there is fastened on said member, in such a manner that the is no longitudinal friction which might impede the useful curved pro?le of said spring substantially lies in the prolongation of said fulcrum line. movement of the said member 3. ‘FIGURES 5 and 6 illustrate two constructional variants 5. In an electrical relay comprising: a yoke in form of of the spring. In FIGURE 5, the spring is a rectangular 30 an angle-member and of a core bearing an energization plane leaf ?xed by rivets on the one hand to the member 5 and on the other hand to the armature 3, which com coil, an armature an end of which lies on a part of said angle-member which make up a fulcrum line and one prises two bearing surfaces situated on either side of the spring. In FIGURE 6, the spring comprises two arms leaf-spring secured to said armature and to said yoke to maintain said armature in return position, the improve 2a and 25 each fixed to two arms 5a and 5b of the mem 35 her 5, the attachment between the members 2 and 3 not being illustrated in the ?gure. The spring could consist of non-magnetic material such as bronze and could be situated below the armature in such manner that a residual air gap equal to the thickness of the said spring is automatically maintained the said spring comes into contact with the core of the electro magnet during the contact of the armature with the off normal contact or contacts. References (liter! in the ?le of this patent UNITED STATES PATENTS Such an arrangement is illustrated in FIGURE 5. ment consisting in that said leaf-spring, which is initially plane in released, free condition, has one end secured on a lug fastened on said angle-member part, said lug being located and obliquely oriented so that, after assembly, said spring is curved while assuring ‘for itself the accu rate position of said armature with respect to said yoke. 4 In addition, the spring may be simply soldered to the 2,061,920 2,423,116 Piifath ______________ __ Nov. 24, 1936 Price _________________ __ July 1, 1947 307,138 Great Britain _________ __ Mar. 7, 1929 armature. I claim: 1. In an electro-mechanical relay having an energize tion winding, a magnetic yoke, and an armature, an 50 extremity of which lies by a fulcrum line on a part of said yoke extending laterally to said winding, the im provement consisting of a bracket laterally ?xed on said FOREIGN PATENTS OTHER REFERENCES Telefonbau, German application Serial No. T5719, printed 1956.