Патент USA US2117047код для вставки
May 10, 1938/ J. H. WHEELOCK 2,117,047 CIRCUIT CONTROLLING DEVICE Filed D80. 26, 1931 3 B, 6a h 7\\ ’ a i i 5ai K‘; 3 Sheets-Sheet l P“ < i l 6 ' v l ' k i . 5// 4‘ ___l ' Mills‘ »1 4 Fig.1. 9 Ba. * @ ® Q) ® ’" "3' 10 ‘ 10a W \11 ‘1a3o. O . 3;?‘ 3 3“ \ @ A 12 Q 1 7M 00 @ O 13 14 12 @ Fig.2. Inventor"; john 7/. ZU’heelock 1'9 WM” 7 ' Attorneu May 10, 1938. ~ J, H, WHEELOCK 2,117,047 CIRCUIT‘ CONTROLLING DEVI CE Filed Dec. 26, 1931 3 Sheets-Sheet 2 lnu'enltov; john H. LU’heelock Bu Alt’corneg I May 10, 1938. .1. H. WHEELOCK 2,117,047 CIRCUIT CONTROLLING DEVICE Filed Dec. 26, 1931 5 Sheets-Sheet 3 Inuenior john H. wheelock 5’ Atiorine Patented May 10, 1938 2,117,047 UNITED STATES PATENT OFFICE 2,117,047 CIRCUIT CONTROLLING DEVICE John H. Wheelock, Fitzwilliam, N. H., assignor to Signal Engineering & Manufacturing Com» pany, New York, N. Y., a corporation of Massa ohusetts Application December 26, 1931, Serial No. 583,319 2v Claims. The present invention relates to circuit con trolling devices, and has for its object to pro vide a device of this character that is adapted to interrupt the flow of electrical currents with out destructive arcing between the contacts thereof. The device of the present invention relates particularly to a circuit controller, of the type employing a pivoted magnetic armature, adapt 10 ed by its movement to carry contacts into and out of engagement, the device in its operation being characterized by the substantial elimina tion of destructive arcing between its contacts, due to an improved manner of breaking the arc ” in the travel of the contact carrying armature. Other results obtained by the invention are re duction of the operating current required, as well as reduction in size of parts, as compared to prior devices of the same current carrying capacity. The above and other advantageous features of the invention will hereinafter more fully appear from the following description with reference to the accompanying drawings, in which: 5 (Cl. 175—375) gization of the winding 3 permitting the arma ture 4 to fall back into the position of Fig. 4, under the influence of gravity. ‘ The armature A carries upwardly extending contact arms 5 and B, terminating in contact tips UK 5a and 6a, and the insulating base I carries stationary contacts ‘I and 8 spaced apart sub stantially the same distance as the contact tips 5a and 6a, respectively. As indicated in Fig. 2, current from a suitable source 9 is supplied to the stationary contacts 1‘ and 8 through conduc tors Ta and 8a, respectively, an electrical load 10, represented by any current consuming device being connected in one of the conductors ‘la or 8a‘. The terminals of the energizing winding 3 are also shown as being connected to the source 9 through conductors 3a, a control switch ll be ing provided in one of the conductors 3a where by the winding 3 may be energized, or deener gized, at will. 20 Assuming that the parts occupy the position of Fig. 4, that is with the winding 3 deenergizecl due to the switch I! being open, it is to be noted Fig. 1 is a view in side elevation of a circuit that the ?exible contact arms 5 and 6 are so controlling device embodying the invention, with formed that the contact tip 5a. is considerably nearer to the stationary Contact '1 than the up per contact tip 6a is to the stationary contact its contacts closed. 2 is a view in front elevation of the device shown in Fig. 1. Fig. 3 is a View similar to Fig. 1, showing the 30 contacts of the device partially open. Fig. 4 is a View similar to Fig. 1, showing the contacts of the device entirely open, with the circuit broken. Fig. 5 is a view in front elevation showing a modi?ed form of the device. Fig. 6 is a view in side elevation of the device shown in Fig. 5. Fig. 7 is a view in front elevation showing a further modi?cation of the device particularly ~10 adapted to handle heavy currents. Fig. 8 is a view in side elevation of the device shown in Fig. '7. Like reference characters refer to like parts in the different ?gures. Referring ?rst to Figs. 1 and 2, the invention is shown, for purposes of illustration, as being embodied in a relay, the essential elements of which comprise an insulating base I carrying a U-shaped magnetic core 2, the shorter leg of which is surrounded by an energizing winding 3 with a magnetic armature 4 pivotally sup ported by the lower end of the longer core leg. With the structure shown, energization of the winding 3 is adapted to attract the armature A and hold it in the position of Fig. 1, deener 8. Therefore, when energization of the winding 3 by closure of the switch I 1 causes the armature 4 to be swung upwardly toward the shorter core leg, the contact 5a ?rst engages the stationary contact ‘I, while the contact tip 6a is still sep arated from the contact 8, as indicated in Fig. 3, this sequence of operation being of importance, as will hereinafter appear. In this position of 35 parts, no current from the source 9 is ?owing through the load l0, although both of the con tact tips 511 and 6a are under voltage from one side of the source 9, through the series connec tion of the contact arms 5 and 6. As the arma ture 4 completes its upward movement, as in dicated in Fig. 1, the contact tip 5a slides some what on the stationary contact ‘I, the accom panying flexure of the arm 5 maintaining the contact pressure. Therefore, when the upper contact tip 6a. engages the stationary contact 8, with some flexure of the arm 6, the connection of the load In to the other side of the source 9 is completed and current flows through the load while the winding 3 remains energized. Upon deenergization of the winding 3, as by opening the switch H, the armature 4 is free to move downwardly, under the in?uence of grav ity, aided to some extent by the tendency of the de?ected contact arms 5 and 6 to resume their 2 2,117,047 normal un?exed condition. As the armature it starts its downward movement, the contacts are disengaged in the reverse order of their closing, so that the contact tip to leaves the stationary contact 8 while the contact tip 5a still remains in engagement with the stationary contact 'i, as indicated in Fig. 3. Under conditions of current flow through the load Iii, there always exists a tendency for an arc to be drawn between the 10 contact tip E0; and the stationary contact 8, as the bus bar H with the arms l9 the same length as the upper contact arms l5 and with the arms 20 slightly longer than the arms l6. With the armature 4 in an open position as shown, the con tact arms l5 and I9 are in engagement with two sets of spaced stationary contacts 2| and 22 located on opposite sides of the pivotal axis of the armature 4. At the same time, the lower set of contact arms 26 are in engagement with a series. of spaced stationary contacts 23, all con 10 the tip 6a leaves the contact 3, but with the de vice of the present invention this arc is quickly extinguished before it attains su?ilcient intensity to be destructive to the contact surfaces, owing to the separation of the contact tip 5a from the other stationary contact ‘I, as indicated in Fig. 1i. In considering the operation of the device as described above, it has been found that the break ing of heavy currents can be accomplished with out destructive arcing between the contacts, be nected to a bus bar 24 carried by the insulating base Ia. With the bus bar 24 connected to one side of the source 9, obviously current will be dis tributed to separate circuits leading from the con tacts 2| and 22. Upward movement of the armature 4 upon energization of the winding 3 will ?rst cause par tial opening of the different load circuits as the longer arms l5 and i9 separate from the station cause of certain inherent characteristics of the device, which may be brie?y summarized as fol separation of the shorter contact arms 20 from the stationary contacts 23 causes breaking of all the circuits with an accelerated increase of air gaps. As the armature 4 completes its closing lows. In the ?rst place, when the contact tip 6a ?rst starts to leave the stationary contact 8, upon deenergization of the Winding, the rate of down ward movement of the armature is at a minimum, with the armature speed increasing rapidly from zero as it falls. Therefore, it follows that any arc between contact tip 6a and contact 8 is formed ary contacts 2| and 22, respectively, after which movement, immediately following disengagement of the contacts 20 from the contacts 23 as de scribed above, the contact arms |6 on the upper side of bus bar I‘! engage a series of spaced sta tionary contacts 23a connected by a bus bar 24a, at the time of their ?rst separation, when the armature starts to drop and the air gap in the cir which is connected to the same side of the source 30 cuit is small. contact arms l5 and I9 under voltage, so that when these arms engage the second series of But before any such are can reach a destructive intensity, the air gap is suddenly increased at another point in the circuit by the separation of the contact tip 5a from the contact ‘I, at a speed very much greater than the initial speed of separation of the contact tip 6a from the contact 8. In other words, by the time the con tact tip 5a leaves the contact '|, the freely falling armature has accelerated to the point where the separation between these contact surfaces occurs at relatively high speed, and this accelerated in crease in the air gap breaks the load circuit. Another factor entering into the separation of ‘ the contact tip 5a from contact ‘i, without ap~ preciable arcing, resides in that any arc initially drawn between the contact tip to and contact 8 reduces the voltage at which the circuit is subse quently broken between contact tip 5a and contact 1. Furthermore, the provision of separate con tact arms on the armature 4 cooperating with separate stationary contacts connected to oppo site sides of the source 9 makes it possible to con trol the circuit without the utilization of ?exible -1 221 conductors leading to the movable contacts, and this general arrangement is applicable to meet a Wide variety of circuit conditions. As shown in Fig. 2, the armature 4 carries two pairs of similar contact arms 5 and 6, each connected to the arma ture by a bar l2 insulated therefrom at I3, and since the opposed ends of the contact carrying bars l2 are separated by an interposed insulating spacer It, the circuits controlled by the respec tive pairs of arms 5 and 6 are electrically inde— pendent of each other. This places all of the longer spaced contacts 2|a and 22a current will be dis tributed to the separate circuits leading from these contacts. Obviously, downward movement of the armature 4, upon deenergization of the winding 3, will ?rst cause disengagement of arms l5 and I9 from contacts 2 la and 2211, followed by the disengagement of arms Hi from contacts 23a. Thus, the device of Figs. 5 and 6 is adapted to break a multiplicity of circuits without destructive arcing, due to the accelerated increase in air gaps in all the circuits being broken, in either direction of movement of the armature. Referring now to Figs. '7 and 8, there is shown a further modi?cation of the device for control ling a large number of separate load circuits, this form of the device being particularly adapted to handle heavy currents in a single piece of appa~ ratus. As best shown in Fig. 7, the device em ploys a pair of energizing windings 3a, 3a with corresponding armatures 4a, 4a supporting be~ tween them a common from at 26. The bus short contact arms 21 of stationary contacts bus bar 25 insulated there bar 25 carries a series of adapted to engage a series 28 connected by a bus bar 29, the bus bar 29 being in turn connected to one side of the source 9, as indicated. The movable bus bar 25 also carries two series of oppositely extending long contact arms 36 and 3| of equal length with respect to the pivotal axis of the armatures 4a, the upper arms cooperating with spaced stationary contacts 32 mounted on the insulating base la. Referring now to Figs. 5 and 6, there is shown a modi?cation of the device for controlling a number of separate load circuits in parallel, with both positions of the armature 4 being utilized to cause the engagement of different contacts. As best shown in Fig. 6, a number of pairs of con tact arms l5 and I6 are mounted on the upper side of a common bus bar I? carried by the armature 4 and insulated therefrom at Hi. 9 as the bus bar 21!. In addition, 75 other pairs of contact arms is and 29 extend below The lower set of arms 3| co operates with a series of stationary contacts 33 mounted on separate brackets 34 supported by the base la, the air gaps between the contact arms 30 and 3| and the stationary contacts 32 and 33 respectively, being the same. As will be evident from a comparison between 1i and 8, the air gaps between the short con— tact arms 21 and the stationary contacts 28 are substantially the same as the air gap between an arm 5 and contact ‘J, so that the operation of the 75 2,117,047 device of Fig. 8 is the same as the operation of the device of Fig. 4, with respect to the making and breaking of the circuit, without destructive arcing. As indicated in Fig. 7, all the stationary tion, a source of electrical energy, a current con~ contacts 32 and 33 are connected separately and in parallel to the other side of the source 9 suming device connected to one side of said source, and a circuit controlling device providing through electrical loads 35, so that pulling up of the armatures 4a in response to energization of the windings 3a results in ?rst energizing the bus 10 bar 25 from one side of the source as the contact arms 2‘! engage contacts 28, and then completing the circuit simultaneously through all of the loads 35 as the arms 30 and 3| engage the stationary contacts 32 and 33, respectively. Obviously, upon deenergization of the windings 3a, the dropping back of the armatures 4a will result in breaking the large number of load circuits without destruc tive arcing, due to the accelerated increase in air gaps between the arms 21 and contacts 28, which air gaps are in parallel with all of the load circuits. 30 3 I claim: 1. Apparatus for controlling the flow of current in an electrical circuit comprising, in combina a pair of spaced stationary terminals insulated from each other and connected to the other side of said source and to said current consuming de vice, respectively, said circuit controlling device 10 further providing a pivoted member free to fall in one direction of movement and electrically connected contacts movable with said pivoted member co-operating with said stationary ter~ minals for creating a gap in said circuit at one 16 terminal at one speed, and for increasing the gap in said circuit at the other terminal at an ac celerated speed determined by the rate of falling of said pivoted member. 2. Apparatus for controlling the ?ow of current 20 in an electrical circuit comprising, in combina From the foregoing, it is apparent that by the present invention there is provided an improved circuit controlling device characterized by the substantial elimination of destructive arcing be tween its contacts, due to the provision of means for successively creating gaps in the load circuits a pair of spaced stationary terminals insulated 26 from each other and connected to the other side of said source and to said current consuming de at an increasing rate. vice, respectively, said circuit controlling device As a result, a device em bodying the present invention is adapted to han dle heavier currents than prior devices of the same rating, with a reduction in the current re quired for energizing the operating Winding. This latter advantage is due to the fact that the device may operate with a smaller air gap between ar mature and core when employing the principle of an accelerated increase of air gap in the circuit being broken. tion, a source of electrical energy, a current con suming device connected to one side of said source, and a circuit controlling device providing further providing a electrically connected engagement with said circuit therebetween, pivoted member carrying ?exible contact arms for 30 terminals to establish said said contact arms being adapted to successively disengage said terminals at different rates of contact separation, in re sponse to free movement of said pivoted member under the in?uence of gravity. JOHN H. WHEELOCK.