US2256653A - Electrical relay - Google Patents

Description

ept- 23, 19 c. s. SN AVELY 2,255,553

ELECTRICAL RELAY Filed Feb. 6, 1940 25 insulation (@DdT 76 Fi 5. [n.sulmion j 2% 70 Fig. 4.

fnsu Zaz'on HIS ATTORNEY i Patented Sept. 23, 1941 UNITED STATES PATENT OFFICE ELECTRICAL RELAY Clarence s. Snavely, Pittsburgh, Pa., assignor to The Union Switch & Signal Company, Swissvale, Pa., a corporation of Pennsylvania Application February 6 Claims.

My invention relates to electrical relays, and particularly to polar relays suitable for use in centralized trafllc controlling systems for railroads, such for example as that disclosed and claimed in Letters Patent of the United States No. 2,183,155, issued December 12, 1939, to myself and others, for Remote control systems.

One object of my present invention is to provide improved means for securing in their properly aligned positions the pivots which support the armature and associated movable elements of a polar relay of the type described and claimed in my prior Patent No. 2,140,604, granted on December 20, 1938, for Electrical relays.

In accordance with my invention, I secure the one pivot support to the relay frameby means of bolts which pass through clearance holes in the support and the frame, and the heads of which engage the support at its outer side. These bolts are made somewhat longer than the thickness of the frame, and I secure the other pivot support to the projecting ends of these bolts by providing this other support with cavities which receive the projecting ends of the bolts and which are filled, after the parts have been properly positioned by suitable jigs, with a substance that can be applied in a liquid, plastic or semiplastic-state and will subsequently set or harden.

Other objects and characteristic features of my invention will appear as the description proceeds.

In the accompanyingv drawing, Fig. 1 is a front elevational view showing one form of relay emboding my invention, the front and rear cover plates of the relay being removed to better illustrate the construction of the operating parts. Fig. 2 is a sectional view taken on the line II--II of Fig. 1. Fig. 3 is a view of the relay pivot bracket l8 as viewed from the rear of the relay. Fig. 4 is a detail view of the contact finger 81 forming part of the relay shown in Figs. 1 and 2, as it appears at one stage in the manufacture of the relay. Fig. 5 is a view similar to Fig. 4 showing the finger 31 as it appears at a later stage in the manufacture of the relay.

Similar reference characters refer to similar parts in each of the several views.

Referring to the drawing, the relay to which i I have shown my invention applied is of the type described in detail in my prior Patent No. 2,140,604, and for a detailed description of this relay reference is made to my prior patent wherein the various parts are designated by the same reference characters as are used in the present application to designate these parts.

6, 1940, Serial No. 317,577

In general, the relay comprises a. rectangular frame I of insulating material that can be readily moulded, such for example as a phenol condensation product, which frame supports all of the operating parts of the relay. Mounted on one side of the frame I are two U-shaped yokes 6 and 'I of magnetizable material. These yokes are disposed with their upper and lower legs in spaced parallel confronting relation to provide the necessary armature air gaps,-and are constantly magnetized by a pair of permanent magnets only one of which is visible in the drawing.

The relay also comprises an armature 24 of suitable magnetizable material such as silicon steel moulded into an insulating member 23 adjacent the rear end thereof. The member 23 is pivotally mounted on front and rear pivots l8 and 19 secured respectively to front and rear pivot supports l and I8. These pivots supports l5 and I8 are secured to the frame I in a manner which embodies my present invention and which I shall describe in detail hereinafter. The upper and lower ends of the armature 24 extend between and cooperate with the confronting ends of the upper and lower legs of the magnetizable yokes 8 and I in such manner that the armature is free to swing between a normal extreme position in which a core pin 24a secured to the upper end of the armature engages the end of the leg 6a of the yoke 6 and a. core pin 24b secured to the lower end of the armature engages the end of the leg lb of the yoke 1, and a reverse extreme position in which the core pin 24a engages the end of the leg Ia. of the yoke 1 and the core pin 24b engages the end of the leg 61) of the yoke 6.

The operating winding of the relay comprises two coils 26 and 28 mounted on spools 25 and 21 which surround the upper and lower ends of the armature with suflicient clearance to permit the necessary movement thereof. The coil 26 is connected by means of leads 26a and 26b to coil connectors 29a and 29b moulded into the opposite sides of the frame I, and the coil 21 is similarly connectedby means of leads 21a and 21b to coil connectors 30a and 30b which are likewise moulded into the opposite sides of the frame i. In practice, the cells 26 and 28 will usually be connected in series. in an operating circuit which is at times supplied with current of normal polarity and at other times with current of reverse polarity.

Moulded into the forward end of the insulating member 28 are four flexible contact fingers 35, 36, 55 81 and 38. These fingers extend toward the four corners of a rectangle and cooperate at their outer ends with fixed normal contact members 35a, 36a, 31a and 38a and fixed reverse contact 7 members 35b, 36b, 31b and 38b, respectively, which are moulded into the sides of the frame l.

The front-and back contact members are'each I The parts are so proportioned thatwhen the armature is midway between its normal and reverse positions, the contact button E1 on each finger will be midway between the contact button 48 on the-associated normal and reverse fixed contact members, as shown in the drawing, but that, when the armature is swung to its normal extreme position, the contact button 41 on the fingers w l then engage the contact button 48 on the fixed contact members to close normal con-. tacts -3512, 36-3641, 31-3Iw and 38-38a,

and that when the armature is swung to its reversed extreme position, the contact button 41 on the fingers will then engage the contact button #38 on the reverse contact members to close reverse contacts 35-35b, 35-3612, 31-4112 and 38-381). The parts are further so proportioned that when the armature occupies either its normal or its reverse extreme position, the flexible contact fingers will be flexed a slight amount intermediate their ends, whereby an efiective low resistance contact is provided between the cooperating contact buttons.

The portion of the relay thus far described is identical with that described in my prior patent, and it will be understood that the armature will move from its central position in which it is shown in the drawing to close the normal or re-. verse contacts according as the relay winding is supplied with current of normal or reverse relative polarity. It will also be understood that the relay armature will be magnetically retained in either extreme position to which it is moved until operated to the opposite extreme position by supplyingthe relay winding with current having a polarity opposite to that which was last supplied to the winding.

According to one feature of my present invention, the contact fingers 35, 36, 31 and 38 are connected by means of flexible flat spring connector members 65, 6t, 61 and 68, respectively, with circuit connectors 43, 44, and 48 which are moulded into the frame I above and below, as the case may be, the coil connectors 23b, 29a, 30a and 30b. As will be noted from an inspection of the drawing, the connector members are bent into a substantially U-shape, and are secured at one end to the fingers by means of the contact buttons 41, and are secured at the other end to the circuit connectors by means of rivets 43a, 44a, 45a and 46a. While the fingers are being moulded into the member 23, the fingers are positioned in the mould through the medium of notches similar to the notch It shown in the finger 31 in Fig. 4, which notches facilitate gripping the fingers. The fingers are moulded into the member 23 before the fiat spring members 65, 66, 61 and 68 and the contact button 41 are assembled. When the moulding operation is completed, the connector members are then riveted on to the fingers by means of the contact button 41 and the saw cut ii is made, after which the end 12 is cut oi! at the line 73.

One advantage of securing the fingers to the circuit connectors 43, 44, 45 and 46 by means of the spring connector members in the manner just described is that the spring connector members are much more stable than the usual type of flexible connectors since they may be readily designed so that they will not break or take a permanent set due to fatigue. This fact is particularly important when relays must operate as many times as is necessary to permit them to be satisfactorily utilized in centralized trafiic controlling systems, since it eliminates the necessity for any replacement of the spring connector members.

Another advantage of securing the fingers to the circuit connectors 43, 44,745 and 46 by means of the spring connector members in the manner just described is that since the spring connector members are secured to the fingers'at the buttons, no current passes through the main portions of thefingers, so that if for any reason more current flows through the contact than it will stand, the fingers will not become overheated and thus anneal.

The means referred to hereinbefore for securing the front and rear pivot supports l5 and I3 to the frame I comprises two bolts l5 and I6. These bolts extend through clearance holes provided in the front pivot support it and aligned holes l1 and 18 formed in a pair of inwardly extending lugs l3 and i4 moulded onto the frame I at its medial portion, and are secured in place by means of nuts 19 and screwed onto the threaded ends of the bolts. The threaded ends of the bolts project beyond the nuts for some distance, and extend with considerable clearance into cavities 8i and 82 formed in the rear support 18. Surrounding the bolts within the cavities 8| and 82 are massm 83 and 84 of a material which can be inserted into the cavities in liquid, plastic or semiplastic condition and which will subsequently harden. For example, the masses 83 and 84 may comprise 7 per cent antimony lead because of its ability to set without shrinkingor expansion. The front pivot support I5 is preferably of metal, but the rear pivot support while it may be made of metal, preferably comprises a moulded piece of material such asa'phenol condensation product because of the greater ease with which it can be constructed.

In assembling the member 23 to the relay, the

front pivot bracket I5 is first clamped. against the forward sides of the lugs l3 and II by means of the bolts 15 and I6 and the associated nuts 19 and 80. The drive element along with the coils 28 and 28 are then put in place, after whichsuitable jigs are inserted between the ends of the armature and the confronting ends of the yokes 6 and I to accurately position the armature with respect to the ends of the yokes. The relay is then laid on its forward face with the threaded ends of the bolts 15 and 16 extending outwardly, and the rear pivot bracket I8 is placed in the position in which the cavities 8| and 82 receive the threaded ends of the screws -15 and 16 and the pivot l9 extends into the pivot opening-in the member 23. The masses 83 and '84 are then inserted into the cavities v and are allowed to harden, thereby accurately fixing the member 23 in the proper position for the armature to coact with the yokes 6 and I and the flexible contact fingers to cooperate with the fixed front and back contact members. The jigs used to hold the parts in place during this operation are then removed.

One advantage of securing the pivot support to the frame in the manner just described is that due to the floating in of the rear pivot support l8, the member 23 is accurately positioned without setting up any stresses in its parts, so that when it is subsequently allowed to move freely by the removal of the positioning jigs, its relation to the cooperating parts will be correct. Furthermore, the desired contact alignment can be obtained without the necessity for too close manufacturing tolerances. This is of great importance when large numbers of relays are manufactured on a production basis, and facilitates holding the manufacturing cost to a minimum.

Although I have herein shown and described only one form of relay embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In an electrical relay comprising a pivoted armature and electromagnetic means for actuating said armature and combination of a frame which supports said electromagnetic means provided with two through holes, bolts extending through said holes, a first pivot support for said armature secured ,to one side of said frame. by said bolts, a second pivot support provided with cavities which receive said bolts at the ends opposite to said first support with considerable clearance, and masses of material in said caviport for said member provided with cavities which receive with clearance the ends of said bolts, said second support being secured to said bolts in a preadjusted position by cementing material surrounding said bolts within said cavities.

3. In an electrical relay comprising a pivoted contact carrying member and electromagnetic means for at times rocking said member to operate contacts, the combination of a frame provided with a pair of through holes, a first pivot support for said member secured to said frame by means of bolts passing through the support and through said holes, and a second pivot support for said member provided with cavities which receive with clearance the ends of said bolts and secured to said bolts in adjusted posi-- tion by means of masses of type metal surrounding the ends of said bolts within said cavities.

4. In a polar relay comprising a frame, two U-shaped constantly magnetized yokes secured to one side of said frame with their ends in spaced confronting relationto form airgaps, a member adapted to be pivotally attached to said frame and provided with an armature having its ends disposed in said air gaps, a winding surrounding said armature, and cooperating contact members carried respectively by said frame and said member, the combination of a pair of lugs formed on said frame and provided with through holes, a first pivot support for said member secured to said frame by means of bolts passing through the support and through said holes, and a second pivot support for said member provided with cavities which receive with clearance the ends of said bolts and secured to said bolts by material disposed in said cavities and allowing initial relative adjustment of said second pivot support relative to said first pivot support in all directions to permit accurate pivot alignment.

5. The method of securing a pair of supports for the pivots of a pivoted member to a frame in a manner to insure correct pivot alignment which consists in bolting one support directly to the frame, accurately positioning said pivoted member with respect to said frame, and forming in the other pivot support cavities which receive the ends of said bolts with sufiicient clearance to permit proper pivot alignment with said member in its fixed position and filling these cavities with a material which is applied in a liquid, plastic or semiplastic state and subsequently hardens.

6. In combination, a frame provided with a pair of through/holes, a first pivot support clamped to said frame by means'of bolts passing through said holes, a second pivot support provided with cavities which receive with clearance the ends of said bolts, 9. member pivotally mounted on pivots carried by said pivot supports, and means for securing said second pivot support to said bolts to insure correct pivot alignment and accurate positioning of said member with respect to said frame comprising material disposed in said cavities around said bolts and allowing initial relative adjustment of said sec

Images